The Pennsylvania's four single-track East River Tunnels were bored in 1904-1909 as part of the Pennsy's massive Pennsylvania Station project, connecting the station with Sunnyside Yard on Long Island; they were also used by Long Island Rail Road trains. When the Hell Gate Bridge and associated trackage was completed in 1916 the tunnels also became part of a through route to Boston. Today they are part of Amtrak's Northeast Corridor but continue to be used by LIRR trains as well.
Here we see one of the East River tunnels as seen from the rear of Amtrak's TurboTrain, looking west towards New York City.
