The High Line may be all the rage these days, but one block away from that famous elevated park stretches a 5-mile-long recreational space that has transformed the city over the past decade. Covering 550 acres (400 of which are on the water) and running from Battery Park at Manhattan's southern tip to 59th St in Midtown, Hudson River Park is Manhattan's wondrous backyard. The long riverside path is a great spot for cycling, running and strolling.
Several boathouses (including one in Chelsea near W 26th St and another in the West Village near Houston St) offer kayak hire and longer excursions for the more experienced. There's also beach volleyball, basketball courts, a skate park and tennis courts. Families with kids have loads of options, including four playgrounds, a carousel (off W 22nd St), mini-golf and grassy piers for young legs to run free.
Those who simply need a break from the city come here to loll on the grass for a bout of people-watching and river contemplation, while those seeking something less sedate can join the sangria- and sun-loving crowds at the dockside Pier 66 Maritime. The park is also a fine spot for watching the sunset. In summer the grassy lawns and converted piers host a wide range of free events, from open-air film screenings and blues jams to dance parties and 'rumbles on the river' (featuring muay Thai kickboxing).
The park is constantly expanding onto new piers along the river, which means you may find stretches along the walking and biking trails that are less than scenic due to construction, and the busy West Side Hwy runs next to the park. It's best to pick a pier to visit and head straight there, as opposed to meandering from location to location.