Greater Greater Washington

Posts about Cars


Self-driving cars are coming, and they could change everything we know about cities

Autonomous, self-driving vehicles are getting more attention from the media, but little from transportation planners. Given the technology's potential impacts on our transportation network, it's time for planners to start thinking about it.

Photo by Dave Schumaker on Flickr.

As the technology advances, mainstream media now treat self-driving cars with seriousness and respect, as do business advisors like KPMG. Developers are designing self-driving car use into future retirement communities, while carmakers like Mercedes advertise passive "self-driving" safety features. Analysts predict that completely autonomous cars will be on sale by 2020.

Self-driving cars have the potential to reduce both car crashes and traffic congestion, and to use wasted time driving for work or entertainment. These are benefits usually attributed to transit; as a result, autonomous vehicles could strengthen arguments for designing for more cars in our cities and suburbs, instead of more pedestrians, cyclists, and placemaking.

Transportation planners aren't talking publicly about driverless cars

By contrast, online searches for "transportation planning" and "self-driving cars" turn up thoughtful, if skeptical reviews by urbanists Todd Litman and Jarrett Walker; a sober, academic summary of key issues by the Eno Center for Transportation; and a thorough debate from 2011 on the issue here on GGW; and an article from Governing Magazine that exemplifies the public preoccupation with regulating driverless cars rather than planning and policy issues.

There isn't a lot of evidence of transportation planners at public agencies giving serious attention to the matter, at least not publicly. A recent blog entry from Bacon's Rebellion also concludes that transportation planners are not paying attention. Though, to be fair, the topic was covered at a recent Florida Department of Transportation conference and the Transportation Research Board a few weeks ago.

Self-driving cars address many of the safety and travel efficiency objections that Smart Growth advocates often make about road expansion, or the use of limited street space. As a result, planners and placemaking advocates will need to step up their game.

They need to better define in what environments bike- and pedestrian-oriented designs are still appropriate even when we can solve our congestion problems with self-driving cars. They need to promote street and intersection that can work for bikes and pedestrians as well as for self-driving cars; and to make a strong cases for Smart Growth and TOD that are based on diverse benefits, not just on the ability to move people.

Capital planning decisions last for thirty years and beyond. The officials responsible for parking lot and garage building, transit system growth, bike lane construction, intersection expansions, sidewalk improvements, and road widenings need to analyze quantitatively how self-driving cars could affect their plans, and to prepare alternatives in case things change.

How could self-driving cars disrupt the planning process?

Here are two examples of situations where planners may need to adapt to self-driving cars:

Self-driving cars coupled with "smart intersections" that communicate with vehicles to let them pass without traditional stoplight timing could result in less congestion, but may speed up cars in places where cyclists and pedestrians are competing for space. The cars will be faster, but also safer to be around. The question is whether a more efficient auto network outweighs the negative impacts to other parts of the urban environment.

They may also make car use more competitive with bus transit in low-density settings and may erode the demand and need for transit (and paratransit). On the other hand, changed transit economics resulting from driverless buses could mean that extending transit into new areas will make more economic sense in the future than it makes today.

Ways to prepare for self-driving cars

So, what could the region's planners do now to anticipate the potentially sweeping changes that self-driving cars will cause? How can planners today insure that scarce infrastructure dollars are spent on things that might be less needed in the near future?

For example, if intersections can handle more vehicles per hour with self-driving cars than with human-driven cars, they may not need to be widened. Or if transit commuters can get to the station in a self-driving car, park-and-rides may not be necessary, because the car will just drive itself back home.

First, land use, highway, and transit planners should simply acknowledge the issue. They should begin to define how large different impacts may be, when those impacts are likely to occur, what the range of public responses will need to include, and when those public responses may have to start occurring.

Self-driving cars will change patterns of car ownership and travel. Planners need to examine how travel forecasting tools that are based on current patterns of car ownership and use will need to change to adapt to new statistical relationships between population, car ownership, trip-making, car-sharing, and travel patterns.

Because cars that can drive themselves won't stay parked all day, builders and regulators should think about how new parking structures should be designed for adaptive reuse if future parking demand declines.

State and local DOTs should measure how smart intersections could increase the number of vehicles that can use an intersection per hour, and how to design roads and intersections that work for self-driving cars, as well as pedestrians, bicyclists, and the creation of public spaces.

Finally, the region's transit agencies should study how driverless operations could affect operating costs for bus, rail, and paratransit services, and should update their long-range capital and operating needs forecasts to reflect what they learn.

Many aspects of the self-driving car world remain in doubt. That is not, however, a reason to avoid thinking about how to benefit from the capabilities that self-driving vehicles offer. Even if planners are only able to do general studies rather than detailed forecasts, that would still be a useful exercise. Understanding how to adapt our communities for the benefits and challenges of self-driving cars would be a huge step forward.


Cars don't kill people, irresponsible drivers do

Every year, tens of thousands of people are killed in auto collisions. In 2012, there were over 34,000 fatalities in the United States alone. This ad from Pakistani newspaper the Frontier Post puts the issue in context.

Image from the Frontier Post.

Over the past 11 years, I have gotten around primarily as a pedestrian and transit user. I've had far too many close calls with drivers who are distracted or who are acting irresponsibly.

Just yesterday, a driver came to a four-way stop while I was crossing the street. But the driver was turning right, and since there was no traffic approaching from the left, she didn't even come to a stop. In fact, she never looked to her right, where I was entering the crosswalk.

Cars have done a lot for the world, and I'm certainly not proposing that we get rid of them.

But I don't think many people think about the risk and responsibility that comes with putting a key in the ignition. Your trip to the grocery store could easily turn fatal, as it does for thousands every year.

So next time you drive, remember that you're driving a machine that could kill someone. Please use it responsibly.


Do bright clothes stop car crashes? Not at Dunkin' Donuts

Highway officials tell pedestrians to wear bright colors so motorists will see you and won't hit you. So why do drivers still crash into brightly-colored Dunkin' Donuts stores?

A driver crashed into a Dunkin' Donuts in Golden's Bridge, New York in 2010. Photo by Golden's Bridge Fire Department.

An internet search found eight cases just this year of drivers smashing into pink and orange doughnut shops. One store in Brooklyn was hit twice, in June of last year and again in January.

One incident involved a motorist who took ill while driving and died in the collision. Otherwise, only a few people were hurt. But the outcome could easily have been worse if someone had been standing in the wrong place.

The excuses drivers make when they strike pedestrians aren't available when they hit Dunkin' Donuts. "I didn't see it" would lack credibility. "It jumped out in front of me" even more so. It should be easy to assign fault when car and store collide.

Yet police chose not to cite the drivers who caused four of these crashes. (One driver died, the driver of a stolen truck is still being sought, and two police departments did not return my calls.) Law enforcement officers seem to think that motorists are under no legal obligation to control their cars. As a Dover, New Hampshire, police lieutenant explained, a woman who hit the gas pedal instead of the brake and smashed into a doughnut store committed no violation because she was sober and not texting.

Motorists have nothing special against Dunkin'. A consultant on retail store safety estimates that Starbucks might get hit as much as once a week. His advice to merchants is to put bollards out front.

Cars colliding with buildings should not be a normal part of life. They are a signal that our highway system is seriously out of whack.

Roads will never be safe unless drivers are held accountable for their ton of deadly steel. One way to start is with fewer lectures about how pedestrians should dress. If bright colors don't protect Dunkin' Donuts, they won't save those on foot.


How will "connected vehicles" affect urbanism?

A consortium of Virginia schools will soon start testing vehicles in Fairfax County that can talk to each other and their surroundings. But what will "connected vehicles" (CV) really mean for transportation and urbanism?

Photo by Steven Mackay.

Researchers have attached tracking equipment to light poles and other roadside infrastructure in and around Merrifield, including stretches of I-66, Lee Highway, and Route 50. The roadside equipment will communicate with devices about the size of an E-ZPass installed in 12 "connected vehicles," including a bus, semi-truck, cars, and motorcycles.

The devices collect data such as acceleration, braking, and curve handling. Researchers hope that the new system will dramatically reduce highway crashes, increase fuel efficiency, and improve air quality.

"The intersection can say 'there is snow happening right here,'" explains Gabrielle Laskey of the Virginia Tech Transportation Institute. Conversely, if a connected car were to experience a loss of traction, it would relay that information to the roadside devices so authorities would know the precise location of hazardous conditions.

Left: a CV data collection unit. Right: an in-car CV display. Photo from the VTTI.

The research will focus on ways to improve both safety and mobility. "If we can detect initial braking, we can slow vehicles down and message the driver, saying something like 'Slow traffic ahead. Reduce speed to 45 mph' or 'Left lane closed ahead; merge right,'" said VDOT Spokesperson Cathy McGhee.

Study will involve area drivers and "regular" cars

The CV technology will go further than the Active Traffic Management System of overhead dynamic signs VDOT will soon install on I-66. The CV system "can give information directly to the driver and provide an additional level of information," said McGhee.

Although the CV roadside equipment is already in place in Merrifield, the connected vehicles are undergoing final road testing on the Virginia test track in Blacksburg. In January, those vehicles plus another 50 operated by VDOT will roll out on Merrifield highways.

In the spring, researchers will seek out drivers of an additional 200 "regular" vehicles through ads on Craigslist and in the Washington Post. Their cars will receive communication devices similar to test vehicles' which will notify drivers verbally or by tone through a GPS-sized display. Drivers who volunteer for the program will not need specialized driving skills. "We want to use na´ve participants and make these devices as useful and available as a cell phone," says Laskey.

Over the next couple of years, a consortium of research institutions consisting of Virginia Tech, the University of Virginia, and Morgan State University will conduct 19 separate CV research studies, about half of which will have components in the Merrifield test bed, at a projected cost of $14 million.

One study looks at road signs that can switch from "yield" to "stop," depending on conditions. Another examines how to dim or shut off roadway lighting when it is not needed. And a study in Baltimore involves the use of smart phones and looks at safety and congestion issues related to public transit, transit passengers, pedestrians, and bicyclists.

The new CV technology can also work in conjunction with some current safety systems which use video to "see" non-connected items, such as a pedestrian in a crosswalk, then alert the connected vehicle. The system helps connected vehicles operate on the roadways before a fully connected or automated roadway system exists.

How will CV influence our transportation network?

CV technology could change the way we use and design our streets. Since connected vehicles will alert drivers to imminent collisions, CV technology is expected to drop the crash rate at least by 50 percent, according Thomas Dingus, director of the Virginia Tech Transportation Institute, which is coordinating the public-private venture.

Dingus and a CV motorcycle. Photo by the Jessamine Kane-Wiseley.

Connected vehicles will be able to safely travel much closer together than cars can today, vastly improving the efficiency of existing highway infrastructure. At the CV system's public debut on June 6, Governor McDonnell noted that the technology "could do as much to help alleviate congestion as the building or widening of new highways."

Researchers say CV technology could be in widespread use within five years, which Virginia and Maryland should keep in mind as they decide how to spend billions in new transportation funding. Cars traveling closer together will require less space, so road widenings might not be necessary. On already wide streets, the extra space could be used for bike lanes, sidewalks, or landscaping. Building smaller streets not only costs less, but it frees up room for buildings and open space, making communities more compact and preserving land.

If you'd like to learn more about connected vehicles, USDOT is holding a public meeting in Arlington from September 24 to 26. The agenda includes information about the CV safety program and the Intelligent Transportation Systems Strategic Plan for 2015 to 2019.


Congestion isn't just about highways

Trends indicate that Americans are driving less and have diminished interest in owning a car. But what happens when the transportation modes they switch to become as crowded as the highways they left?

Photo by James Lee on Flickr.

In the United States, we usually focus on gridlock and time lost while driving, the "primary mode" for a majority of commuters. For me, and for a growing number of people, driving alone is the "alternative mode" of transportation, a term traditionally used to describe transit, biking, and walking.

Meanwhile, my primary modes of transportation are increasingly congested. I stand in crowded buses and Metro cars, jostling around to let fellow passengers on and off, nearly falling over as I try to read a book or edit a report for work. In order to relieve congestion on all modes, we have to change the way we talk about congestion.

In 2008, Washington D.C.'s Metro identified multiple stations where platforms are overcrowded or will soon be overcrowded, and one of the main purposes of Metro's Momentum plan for investment through 2025 is to relieve crowding in the system's core.

The rapid roll out of bicycle infrastructure in the region is also suffering from success; heavy volume on the 15th Street and L Street cycletracks, as well as where the Custis Trail hits Lynn and Fort Myer in Rosslyn frequently causes backups for me and, based on the queues of cyclists that I see, many others.

Day after day, my colleagues and I at Arlington County Commuter Services send the message that, as transportation demand management (TDM, or mobility management) professionals, we make the transportation system work better. Yet our key measure of success is based on only one portion of the transportation system: the number of automobile trips that we shift off of the road network each day and on to other modes (see graphic below).

When TDM/mobility management is practiced with the goal of removing single-occupancy-vehicle (SOV) trips from the road, it can increase congestion for those of us who do not drive. Where is the TDM/mobility management for people like me?

Infographic from Mobility Lab.

As TDM/mobility management professionals and behavior changers, we must expand our horizons, and work to relieve congestion across all modes in the transportation network. If we do this, we can improve the commutes of the many individuals who, either by choice or by force of circumstances, do not drive. Focusing on all modes will keep our industry relevant for this growing segment of the population.

Using TDM strategies for other modes is not new. A London Underground poster from 1942, which encourages staggered work schedules in order to relieve crowding on the tube, is evidence of how to apply the active outreach and marketing that we use to shift SOV trips to transit.

In our own region, we already see transit-oriented TDM in the form of Capital Bikeshare, which is shifting trips off of the congested Metrorail system. Of course, Capital Bikeshare also suffers from congestion in the form of bike-rebalancing problems.

Broadening the TDM/mobility management industry's sense of responsibility to include the efficiency of the entire transportation system will elevate the importance of transit, biking, walking, and sharing rides in conversations about transportation. Just as we need to eliminate use of the phrase "alternative modes" ("high-efficiency modes" instead?) and the implicit privilege that the phrase gives to driving, we need to stop considering automobile travel as the mode needing management with the support of other modes.

In addition to applying our toolbox of monetary incentives and outreach and education programs to other modes, we also need to measure our programs' success against levels of transit congestion, bike congestion, and the flow of people regardless of mode. Why does this change in measurement matter? As the legendary 20th century management consultant Peter Drucker said, "what gets measured gets managed."

The Texas Transportation Institute's oft-quoted Urban Mobility Reports create buzz and urgency around reducing highway congestion, but we do not regularly talk (or generate panic) about congestion on other modes. In a recent Business Vancouver article, writer Peter Ladner observes that "while car congestion costs are consistently assessed and circulated, the costs of transit congestion are rarely measured and never discussed."

Ladner notes that because the Vancouver public does not discuss transit congestion much, support for transit funding suffers. Thus, if researchers start making regular reports of congestion on other modes, then political support for funding TDM, transit, biking, and walking infrastructure could be easier to obtain.

A multimodal approach to congestion would be beneficial even in regions where there is little congestion on transit or in bike lanes; in a car-dependent region with heavy road congestion and low bus ridership, for example, showing volume and delay on both modes side by side could spark conversations about shifting travel from one mode to the other.

Make no mistake, reducing SOV trips (a "low-efficiency mode?") remains an important and valid TDM/mobility-management goal, and I am proud of the work that Mobility Lab is doing to estimate the number of drive-alone (or SOV) trips that Arlington County Commuter Services takes off of our region's roads. These estimates allow us to compare more readily our work to that of road and transit builders, and I cannot yet offer a comparable equation or method for evaluating our work on the basis of all modes.

However, getting to an efficient, multimodal future requires us to become truly multimodal. In order to advance our efforts we, as the people who create behavior change, need to look at ourselves, and change our own behavior.

Crossposted at the Mobility Lab blog.


When we lost the War on Pedestrians

Every new bike lane, speed camera, or change in parking requirements becomes an attack in what organizations like AAA decry as a "War on Cars." But in the 1920s, there was a different war over our streets. And pedestrians lost.

Photo by Rich Renomeron on Flickr.

At one time, citizens fought to keep their streets for people. But by the 1920s, cars were appearing in ever-greater numbers on the streets of American cities, and the war on pedestrians began. By 1929, motorists could declare victory, and pedestrians, especially children, paid the price.

In April, design-focused podcast 99% Invisible covered the war on pedestrians, from which motorists emerged victorious. Dubbed "The Modern Moloch," the episode is named after the ancient god of the Ammonites, who received children sacrifices in the name of prosperity. A 1923 editorial cartoon in the St. Louis Star depicts Moloch's altar as the grill of a car. Host Roman Mars leads listeners through the narrative.

Before the car became king, streets were for all users. Pedestrians could just stride right out into the street. Traffic on the street, horses, streetcars, and motor cars moved at very slow speeds.

With a growing mass of automobiles, drivers tried to go faster. By 1923, according to the episode, over 17,000 people were being killed by cars each year. That was up from just 12,000 in 1920, a 47% increase. The outcry was loud. People held parades to memorialize the dead, and cities began to propose laws that would make it difficult to drive.

The issue came to a head in 1923, when Cincinnati voters put an initiative on the ballot to require that every car have a governor which would limit speeds. Car manufacturers realized that if it became too difficult to drive in cities, people wouldn't buy cars and instead choose transit or other modes.

The car lobby responded by taking the approach that cars weren't dangerous, people were. Drivers can be reckless, they said, but then so can pedestrians. However, Americans weren't sold on the idea of a reckless pedestrian. The lobby began to use the word "jaywalking" as a way to coerce pedestrians to cross only at corners, mainly though peer pressure. Los Angeles passed the first anti-jaywalking law in 1924.

In 1929, the first cloverleaf in America opened, and motorists could declare victory over pedestrians. Over the following years, cities began to require parking spaces, streets were widened by highway departments. And pedestrians got further and further marginalized in a nation that droves more and more miles every year.

Last December, an episode called "Built for Speed" brings the story forward to the present. What does the design of our streets tell us about driving?

Mars interviews author Tom Vanderbilt, the author of Traffic: Why We Drive the Way We Do. He notes that no matter what speed limit signs tell drivers, the context of our roads often encourages us to drive faster. They also tell us not to walk.

The episode talks about street trees as an example of how the changing design philosophy encourages drivers to go faster and encourages pedestrians to not walk. In the early 20th century, communities planted trees between the curb and the sidewalk, giving pedestrians shade and creating a buffer between the sidewalk and car traffic.

But after World War II, traffic engineers began to rethink the design. At high speeds, a tree can be deadly in a crash. So instead, designers moved the trees to the other side of the sidewalk. This, of course, makes pedestrians the buffer. But it also makes the road feel wider, and that encourages drivers to go faster.

In 2001, 42,196 people were killed in motor vehicle collisions in the United States. That same year, a terrorist attack in September killed 2,996 on American soil. The September 11 attacks were a call to arms for Americans, and resulted in billions being spent on the war in Afghanistan.

The Afghanistan war, now America's longest conflict, has resulted in the deaths of 14,449 allied soldiers (2,260 American troops) and 19,013 civilians, a total of 33,462 over 11 years. In the period from 2001 to present, 460,536 people have been killed in motor vehicle collisions in the United States.

The "War on Cars" may have resulted in fewer fatalities. But last year 32,367 people were still killed in car crashes.

The deaths of almost 3,000 people in terrorist attacks was enough to spur an actual war. But when more than 10 times as many people die in crashes every year, it seems that most consider it just the cost of doing business. These deaths are simply sacrifices to our modern Moloch; the people we sacrifice in the name of prosperity.

And whenever a government tries to make our streets safer, especially for vulnerable users like pedestrians and cyclists, the auto lobby says drivers are victims of a "War on Cars."

Cities around the nation are working on projects to reclaim public spaces in our cities for people. Programs like New York City's Public Plaza projects and other traffic calming initiatives are making streets safer for everyone.

That's not a war on cars, that's a war on death and injury. Pedestrians and cyclists can indeed coexist with motorists. But not when they're marginalized and subjected to missing sidewalks, speeding drivers, and other hostile conditions.

Our communities can be prosperous without offering up our most vulnerable road users as sacrifices. But it requires a rethinking of what our roads are built for. So long as "speed" is the answer, pedestrians and cyclists will pay the price. So will many unfortunate motorists.


Where do Montgomery's car-free residents live?

Like many suburban communities built after World War II, Montgomery County developed based on the assumption that everyone would have a car. However, many households have just one, or none at all. While some are in the county's urban centers, a surprising number are in very car-dependent places.

Where car-free residents live. All images by the author.

According to the 2007-2011 American Community Survey, a sort of annual census, there are over 374,000 households in Montgomery County, and 91.8% of them have cars. That's not surprising for a largely affluent suburban county, where many people own cars simply because they can. Growing up, I had several friends whose parents raced sports cars, but never drove them on the street.

But car ownership countywide is slightly lower than in 2000, when 92.5% of all households had cars. Today, more than 2 out of 5 households have one car or no car. Like transit riders and young adults, those households are concentrated in certain areas, which can give us insight on where to make it easier to get around without driving.

Car-free households cluster around transit

Just 8.2% of the county's households have no car, and you'll find many of them near transit. 5 of the top 10 largest concentrations of car-free households are near Metro stations. Over 30% of all households in Silver Spring and 28% in Twinbrook are car-free. Some concentrations are in older, walkable areas with good bus service, like Long Branch, where over 1/3 of all households have no car. As a result, Long Branch has high transit ridership.

There are also many car-free households in newer suburban areas like Briggs Chaney, where they make up a quarter of the population, and even Germantown and Damascus, where 10% of all households are car-free. These communities have winding, disconnected streets, which can make walking very dangerous and good transit service nearly impossible.

Not surprisingly, retirement communities also have lots of car-free households. Over a quarter of all households in Leisure World and Old Town Gaithersburg, home to the Asbury Methodist Village retirement community, have no cars, while Riderwood Village in Calverton isn't far behind.

These developments don't have great transit or much within walking distance, but they do have a lot of on-site amenities. (But that still wasn't enough to lure my retired aunt and uncle to Leisure World from Columbia Heights.)

Bethesda, Chevy Chase have lots of one-car households

One-third of all county households have one car, a slight decrease from 2000. Like those with no cars, these households are concentrated along major bus routes and in retirement communities. As before, Briggs Chaney and Leisure World top this list.

Where households with one car live.

But there's also a lot of one-car households along near Red Line stations in Bethesda and Chevy Chase. Nearly 2/3 of downtown Bethesda households have one car, but relatively few have no cars at all. This suggests that many Bethesda residents move downtown to have amenities within walking distance, but bring a car anyway.

There are also large concentrations of one-car households along I-270 and Rockville Pike, which appear to coincide with activity centers like White Flint and Washingtonian Center in Gaithersburg. These are places that might support a "car-lite" lifestyle: they have some walkable areas, and in the case of White Flint, a Metro station. But for now at least, they're not dense or pedestrian-friendly enough to leave the car at home all the time.

Households with many cars in suburban, rural areas

Almost 40% of Montgomery County households have two vehicles, and 19% have three or more. But where they live is almost the inverse of where no-car and single-car households are located. Two-car households seem to form rings around the county's Metro stations and activity centers. Many of them are concentrated west of I-270 and in further-out communities like Olney and Clarksburg.

Where households with two cars live.

But 3 of the county's largest concentrations of two-car households are in close-in areas, like Four Corners in Silver Spring and Chevy Chase Village. Four Corners especially sticks out, as car ownership rates are generally lower in East County, and it's a pretty walkable area served by two major Metrobus lines.

Where households with three cars live.

Meanwhile, three-vehicle households are largely confined to the county's Agricultural Reserve and other rural areas. Those third vehicles probably aren't being used for commuting, but for hauling supplies or produce.

Without transit, car-free residents are stranded

The concentrations of car-free or car-lite households in places like downtown Silver Spring or downtown Bethesda show that Montgomery County's efforts to build around transit have encouraged people to drive less. But for the county's growing number of low-income households, going car-free isn't a choice. Places like Germantown and Briggs Chaney are more affordable, but without good transit or walkable neighborhoods, their residents are basically stranded far from shopping, social services, and most importantly jobs, which restricts their economic mobility as well.

A dirt path in Germantown. Many car-free people live in places where it's hard to get around without a car.

How can we fix this? Part of the answer will come in the redevelopment of places like White Flint, which will result in some affordable housing, giving low-income households a chance to live in a place redesigned for walking, biking, and transit. But we'll also have to figure out how to provide better transit and better walking conditions in the neighborhoods where people already live.

One solution could come from the county's Bus Rapid Transit plan. While planners' vision for a network of countywide BRT lines has serious flaws, it does propose improved transit service along corridors where car-free households already live, like Rockville Pike and Route 29.

Most Montgomery County households have cars, and will probably continue to for the foreseeable future. But we still have to make room on our streets for the growing number who don't.

Crossposted on the Friends of White Flint.

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