i-395 and us 1 cross the potomac river from virginia to washington, d.c., on three parallel four-lane bridges, together known as the 14th street bridge. potomac river crossings for the washington metro's yellow line and for a major csx railroad line are immediately downstream here. this site has long been a major potomac river crossing, with the first bridge constructed here in 1809. of the present highway spans, the eastern one was built in 1950, the western one in 1962, and the central one in 1972.