DDOT’s streetcar website has a lot of great resources. All the things you’d expect, like open house dates, construction updates, their new plans and other documents, are there and easily accessed.
They also have a gallery of some great old photos of DC’s original streetcar network.
This image (circa 1943), from the old underground turnaround terminus for the southern end of the 14th line features a nice vintage advertisement for upcoming hockey games at Uline Arena. Looks like Hershey and Cleveland will be in town to play the Washington Lions. Hershey, of course, is now the AHL farm team for the Caps.
Pennsylvania Ave, looking at the Treasury Building, circa 1925.
DDOT’s got a whole slew of historical photos in their online archive, well worth checking out.
Looking north up Connecticut Ave towards Dupont Circle, 1958. Note the two underpass entrances – the nearest for streetcars and the other (currently extant) for cars.
Another from 1958, this is what’s now Freedom Plaza.