Speaking as an inline skater, I can give you lots of gory details. But #BikeNYC peep would know more about this spot.

This is a bridge on the park path that crosses over Amtrak. The bridge is wood, wood beams and plywood, and some years ago, it was in terrible shape and was closed. (There was certainly a streetsblog article about it.) It was repaired not too long after (which in NYC these days means within a year, maybe). It was okay last time I rolled this way, which was a few years ago.

I don't go this way anymore because the overall path from river level up to alongside the parkway can get really steep and really scary.