The west side of Manhattan used to be an elaborate system of rail tracks and train cars that would transport goods from NYC to NJ and vice versa. Eventually that system became obsolete and the trains and their transfer bridges abandoned. Some of this rail system was called The Highline... which you can visit still as a manicured park in the heart of Chelsea. However, some of these transfer bridges aren't as lucky. Though they sit in disrepair in the murky Hudson River, they are protected by the city and will remain as part of the horizon of Riverside Park.