Metro

Twice as High Line

More High Line is on the way.

With 2 million people having visited Manhattan’s park in the sky since it opened last June, officials at the elevated green space say they’re now on track to complete a new, second section of the High Line in time for an opening next spring.

During a tour of the new section, stretching from 20th to 30th streets, enough of the construction has been completed to visualize the array of quirky new landscapes and attractions that will extend High Line Park to a full mile in length.

The most over-the-top feature begins at 25th Street, where work has begun on a “Woodland Flyover” that will lift park-goers 15 feet above the old rail trestle through a stand of magnolia trees.

“The walkway leaves the High Line itself,” said Peter Mullan, the park’s vice president of planning and design. “You’ll be walking through the canopy of trees.”

Mullan said the design for the flyover, like most of the other park features, evolved out of what was found on the long-abandoned rail line before it was cleared to make way for a new park.

Where the trestle runs between hulking warehouses in Chelsea, the High Line once sprouted a small forest of trees and shrubs. That forest will be recreated, this time with magnolia trees.

Between 22nd and 23rd streets, park planners have turned an old railroad siding that was once used to reach into the adjacent warehouses into a feature called the “seating steps” that will rise above a lawn that lifts up on a small hillside.

The second section of park is straighter, with few of the twists and turns of the half-mile of rail trestle that runs from 20th Street south to Gansevoort, where it begins.

Along much of the new section, including the “Chelsea Thicket” at 20th Street, plantings of native and wild flowers will be denser than in the first section of the park.

The elevated trestle will push up through what was once one of the city’s prime industrial corridors — with vestiges of Manhattan’s manufacturing legacy laid bare like a time capsule.

“The High Line gives you a vantage point on the hidden New York that you don’t otherwise get to see,” said Mullan.

tom.topousis@nypost.com