Last week I took this photo. On another snowy day I turned to the left 90 degrees and took this. This might be the highest spot a regular person can get to in the NYC Subway System.
This is the work of 9th grade students at the New York Harbor School.)
So Smith & 9th Street is 91 feed above sea level. Now that there is a temporary staircase going over the platform that goes over the road, 4th Ave might be higher.