For many years in the latter half of the 20th century, few US cities were actively building new transit lines. Yet in 2012 alone, 31 US cities will either open, start, or continue construction on new public transportation infrastructure, mostly rail.

As this map from The Transport Politic shows, the times, they’re a-changin’.

Major transit openings and construction starts planned for 2012.

Image by Yonah Freemark on The Transport Politic.

The map was published as part of an extensive post that lists every major transit line in the US that will either open or be under construction in 2012.

The list is impressive. Nearly every major metropolitan area in the country is represented, and even more would be if the list included projects in the planning stages but not yet slated to begin construction.

The listed projects range from the gargantuan to the mundane. From New York’s Second Avenue subway, to a BRT line in Fort Collins, Colorado.

The three map icons next to Washington indicate DC’s streetcar projects and the two phases of the Silver Line. Other local projects, such as the Purple Line, the Columbia Pike streetcar, and the Corridor Cities Transitway, aren’t shown because they are still in planning.

Our country still has a long way to go before the decades of automobile-focused planning are fully repaired. Even this list, impressive as it may be, is short compared to the highway construction list from most individual states. But still, we’re making progress as a country. We’re doing things now that we weren’t doing a few decades ago. Transit is reaching more people, in more places.

So let’s congratulate ourselves for a solid step forward. But let’s not be too happy; there’s still much work to be done.

Cross-posted at BeyondDC.

Dan Malouff is a transportation planner for Arlington and an adjunct professor at George Washington University. He has a degree in urban planning from the University of Colorado and lives in Trinidad, DC. He runs BeyondDC and contributes to the Washington Post. Dan blogs to express personal views, and does not take part in GGWash's political endorsement decisions.