Head for the Hills! You’ll find plenty of them at Governors Island, the 172-acre oasis off the southern tip of Manhattan, part of which just became a thrilling new playground.

Thanks to a $71 million, ecologically engineered project, recycled debris from demolished buildings created the island’s rolling new grassy slopes along 10 acres of the island’s southern end. The tallest point, 70-foot-tall Outlook Hill, affords breathtaking skyline views, while the longest slide in the city — a curving 40-footer — has kids scrambling back up Slide Hill for return trips.

This being New York, of course, there has to be art, and there is: Rachel Whiteread’s “Cabin,” an inside-out concrete cast of a building some frontiersmen and -women might have slapped together from wood. From its perch overlooking Manhattan, it has the kind of view any real estate speculator would kill for.

Ferries leave from both Manhattan’s Battery Maritime Building (10 South St.) and Brooklyn Bridge Park’s Pier 6 for the brief, breezy trip.

Governors Island is open Saturdays and Sundays from 10 a.m. to 7 p.m., and Monday through Friday from 10 a.m. to 6 p.m.; for ferry information, visit GovIsland.com/info/ferry