The cache is located in the spacious Highbridge Park, one of the largest parks in Manhattan. It's near the end of the magnificent High Bridge itself -- built in 1848 (the oldest standing bridge in the city!) to convey water from the Croton Aqueduct across the Harlem River. The city would never have grown like it did without this vital source of fresh water.
So, you'd think this would be a busy area, wouldn't you? Well, maybe not....
The aqueduct was decommissioned in 1958, and the pedestrian path along the top was closed not long after. Much of the park looks like it hasn't been maintained much since then, either. Plans are afoot to rehab the park and reopen the bridge to pedestrians, but in the meantime, it's a curiously unknown parcel of Manhattan.
The cache is a sandwich-sized plastic container a few hundred feet south of the bridge plaza. There are several ways to its location, with widely varying difficulty -- the shortest path may not be the best. Longer approaches may offer easier terrain and much more attractive surroundings on the way, especially when the plants are in bloom.
Please note: This cache is in an isolated area of the park, so use appropriate caution. I wouldn't recommend visiting at night.