Pier 45
Pier 45, a.k.a. the Christopher St Pier, is a lovely spot to catch some rays. This Hudson River Park pier is 850 feet long and and boasts plenty of lawn space to sprawl out. It also features shady spots, bathrooms, concert space, outdoor showers to cool off in, and of course, beautiful views. Being so close to the water makes tanning feel like an appropriate city activity. Plus, the Pier 45 website literally advertises sunbathing, so you have no excuse not to go.
Pier 45, Greenwich Village at Christopher St, NYC
[Photo via @mandameaux]