A spin around the park on a bike makes me feel good. One lap is about 6.13 miles. I've trained here for longer rides (including this London to Paris ride on a track bike that was 86 miles one day, rest on the second day, and 136 miles on the third day). I've sat there on a Sunday afternoon and have done as many as 10 laps (with rests in between). I switch in-between my carbon road bike and my steel track bike.
Having the experience of owning and running a coral reef aquarium (and frequenting this particular shop about once a week) - I was sad to hear it closed it's doors. Their reef display tank was always amazing. These pictures were taken from PetCo at Union Square (I also used to go there for my saltwater needs).
I live above TriBeCa and take walks into and around this area often. It's quiet, usually on the emptier side, and hosts a few gems of restaurants including Tiny's, Takahachi, and Odeon - all on the same block of West Broadway.