Penn station is.34th st on the west side. Mount Sinai is 100th st on the eastside. Buses would take you forever going uptown. I'd suggest.you walk east from 7th ave past.the empire state building to.park ave (or take a.cross town bus East on 34th street a.few.blocks and.take the 6 train local at park and 33rd st North to 96th and walk back to Madison ave 1 or 2 blocks to the hospital.
You really need to ask someone that works for the mta subway because when you are at Penn Station there you find employees that can direct you.
Oh! You should take the Greyhound bus at the bus station in Pennsylvania to the bus terminal in New York City (at 42nd Street), then take the No. 7 subway to the No. 6 subway to the 98th Street Station, and exit the westbound two blocks. It’s very convenient to go to Madison Avenue.
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