I had the opposite experience! My girlfriend and I walked from the Bronx to Battery Park, it was great. We saw the neighborhoods change from block to block, bought bootlegged DVDs from a sweet old lady, and even ran into Robert Krulwich outside of Central Park. If you have 10 hours it's worth it.

For my 30th bday, some friends and I walked around the perimeter of Manhattan. It took just over 20 hours, but that's mostly because we stopped several at bars along the way.

It's funny because back home in Texas I'd drive that distance (in miles) regularly to do stuff with friends and think nothing of it.

Take a taxi from Harlem to the Botanical Gardens when there's no traffic (so never, or at 3-4am), you'll be surprised how fast you get there.

It's crazy how much longer the same distance feels when you can't just drive straight there with little to medium traffic!

Try Pelham Bay Park (Bronx) to Conference House Park (Staten Island): 35 miles, 10 hours walking! Or Inwood Hill Park (Manhattan) to Rockaway Park (Queens): 25 miles, 8 hours walking.