The incredible site that is the NYC Department of Records Photo Archive showcases the grit and mechanics of the 20th century city. Some of the photographs are iconic, such as
If you go, use the classification tree on the left. The keyword search will find you very little if you type “subway” or “train.”
Check out this image of the Williamsburg Bridge streetcar terminal. The streetcar’s viaducts to the bridge and its kiosks used to fill the grayness that is the middle of Delancey Street today. This is the same space that is slated to become the Low Line underground park if all falls into place. Read more about the tangle of streetcar services and view some other great photos of how to cross from Manhattan to Brooklyn in the early 20th century at Abandoned Stations.