We've probably had a dozen experiences with bike theft over the years. Best thing you can do is have two Kryptonite locks and don't leave your bike on the streets over night.
Otherwise bikes are great for city exploring. You can even take them on MTA, PATH, and regional trains during non-rush hour times which can really expand your reach. You're probably too distracted by all the pretty girls but here's a couple things to do that might be of interest.
https://en.wikipedia.org/wiki/MoMA_PS1
MoMA PS1: Warm Up 2015
Forbes Life - I think totally worth checking out. They have a huge outdoor area and commission different artists and architects to do large scale
installation pieces every year. Then they open the doors, have DJ's, and serve booze to thousands on aficionados on the weekends. Super fun!
https://en.wikipedia.org/wiki/Brooklyn_Bridge_Park -recently completed, great city and bridge views.
https://en.wikipedia.org/wiki/Governors_Island
Governors Island - free
ferry ride from lower manhattan,
events every weekend all summer long.
https://en.wikipedia.org/wiki/Rockaway_Beach,_Queens
https://en.wikipedia.org/wiki/Fort_Tilden
https://en.wikipedia.org/wiki/Coney_...Mermaid_Parade - get your surf on at the Rockaways, your beach on at nearby by Fort Tilden, and get your freak on at the Mermaid Parade!
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