The Highline is a brilliant piece of New York urban recycling. It's a very clever use of a disused overhead railway line. It runs along the west side near the Chelsea Market. Due to it's elevation, the views to the west across the Hudson and to the east across the New York skyscrapers are stunning. It's a sort of elongated, parkland/public space. I'm told that there are great crowds there in the summer. The day I went in December it was very cold and windy. The wind was coming across the Hudson. Not so many people there that day. The old railway line is still visible. There are places to sit and take in the views and catch some fresh air and sunlight.
The plantings are designed to look like the side of a railway track to maintain the original character.
New Yorkers are very proud of this project. There are plans for several extensions.