Lexington Avenue Tunnel was created in 1918.
Greene Avenue - BMT Lexington Avenue Line - ended in 1950.
Tompkins Avenue - BMT Lexington Avenue Line - was created in 1885.
Reid Avenue - BMT Lexington Avenue Line - was created in 1885.
Reid Avenue - BMT Lexington Avenue Line - ended in 1950.
Tompkins Avenue - BMT Lexington Avenue Line - ended in 1950.
BMT Lexington Avenue Line was created in 1885.
IRT Lexington Avenue Line was created in 1904.
BMT Lexington Avenue Line ended in 1950.
There is no subway line under Madison Avenue, although there are bus-only traffic lanes. Two blocks east, the 4-5-6 trains run under Lexington Avenue (and Park Avenue below Grand Central).
Take the Uptown 6 train (of the 4-5-6, the dark green line) from 33rd Street (at Park Avenue) to 86th Street (at Lexington Avenue). Park Avenue is the next avenue east of Madison, and 3rd Avenue is the next avenue east of Lexington.
Bowling Green - IRT Lexington Avenue Line - was created in 1905.