Good places to see unused platforms.

Where's are there good (and legal) places to see abandoned sections of platforms. Or even sections of stations?

IRT City Hall. Ride the 6 (southbound after last stop Brooklyn Bridge), just stay on as the train loops around.

18 Street: Look out of the windows of a 6 between Union Sqaure and 23rd.

On PATH: 19 Street is visible between 14 and 23.

Besides City Hall, is it possible to see any unused entire stations?

Unused platforms in plain sight:

IND 59th st / Columbus Circle
IND Hoyt Schermerhorn

Also Chambers (BMT).

There's one in Syracuse near the stadium.

West side IRT - 91st Street.

On the BMT in Brooklyn - betwen DeKalb and the bridge - old Myrtle Avenue Station.