\[23rd Street Station, IRT East Side Line, Manhattan, NY] 23rd Street Station, 23rd Street and 4th Avenue (now Park Avenue South), Manhattan, NY. Contract 1 construction of the IRT East Side line. Southwestward view of the West station platform, showing terra cotta ceiling moldings, a skylight with circular glass panels, wall tiles, mosaics and terra cotta medallions inscribed with the number 23.