At one time... but... not since Labor Day in 1935...
For a long time after that hurricane that took out the railroad, you could drive out there on the bridges originally built by Florida East Coast RR (which the state of Florida took over, fixed some of the hurricane damage, and in 1938 made part of US 1.)
US 1 was rebuilt in the '80s. Now the remains of the viaducts are used as fishing piers and observation decks as part of the Florida Keys Overseas Heritage Trail...
FEC RR bridge on left, 'new' US 1 on right...