The High Line park opened to the public earlier this year
New York's newest park - built on the tracks of a rusting and half-forgotten railway line - snakes between the skyscrapers of Manhattan, as Jonathan Marcus discovered when he visited this ribbon of greenery set in a concrete jungle.
They call it the High Line, an old elevated railway that threads its way through abandoned warehouses and bright new glass and concrete buildings on Manhattan's Lower West Side.
Abandoned in 1980 - the last train carried three freight cars of frozen turkeys - it simply slumbered for more than 20 years. Nature took over. Grasses and even trees grew up between the sleepers.
It remained largely forgotten, until now. Today, the High Line is one of New York's most unlikely new attractions.
I followed the whole course of the line from ground level. The only real clues to its existence are the cast-iron, Art Deco bridges crossing each side street as the tracks run parallel to 10th Avenue.
At one cross-street, you can still see the fading logo of the New York Central Railroad, which first elevated its street-level tracks to reduce road accidents in the 1930s.
Robert Hammond lived in the area and had come to love the line's rusting steel structure
During its hey-day, trains delivered goods to a variety of wholesale food warehouses, running into - and in some cases through - the buildings that they served.
This was the only rail-freight route into Manhattan that kept its feet dry. All the other railroads had to ship their freight cars over on tug-hauled barges or car-floats.
But the New York Central was special.
Its line ran northwards from a terminal south of Greenwich Village, passing almost unnoticed through some 30 city blocks before entering the West Side Rail Yard and disappearing underground.
Its destination was Albany in up-state New York and beyond.
On the corner of Gansevoort and Washington Street - in the heart of the old Meatpacking District - I met up with Robert Hammond, one of the joint saviours of the High Line.
Originally from Texas, he lived in the area and had come to love the rusting steel structure.
He told me that when he heard that there were plans to demolish it he went to a local council meeting convinced that there must be somebody working to save the line. There wasn't.
It is a masterclass in urban renewal, a kind of 'strip-prairie' through the heart of the urban jungle
At that meeting he met travel writer Joshua David. They discussed starting something and the Friends of the High Line was born.
Ten years later, the first section of the line is now open as Manhattan's newest park.
From the street we went up a new staircase and emerged onto the viaduct into a magical land.
A new pathway has been laid using concrete slabs. This meanders through beds of grasses and other plants, all carefully planned to retain a wild and overgrown look.
Here and there the old railway lines are still visible, with each piece of rail having been returned to its original place. At the start everything had had to be cleared away, Robert Hammond told me, but the structure itself was in surprisingly good condition despite years of neglect. The most expensive thing, he said, was stripping away all of the old lead-based paint.
We headed off northwards under the newly built Standard Hotel which straddles the line. It is brutally modern: "Eastern Bloc meets Miami," as Robert described it.
Its pale green curtains or blinds make it look a bit like a hospital. It seems that some, shall we say, more exhibitionist couples have failed to close those blinds, providing an unexpected show for walkers on the High Line below.
Robert Hammond said that such stories were overblown but this was fast becoming a new urban myth, a token in many ways of the line's extraordinary success.
On this typical sunny Saturday, he expected to have some 25,000 visitors, walkers, joggers, sunbathers, grandparents with their grandchildren - anyone who wants to see the city from a fascinating new vantage point.
You are above ground but not so high that you cannot make eye contact with people in the streets below.
When completed, the park will be one and a half miles long
On one side, you pass Pier 54 on the Hudson River. That is where the Titanic would have docked, Robert told me.
To the right, there is a fine view of the Empire State Building and, if you turn around and look back down the course of the line, you can just make out the Statue of Liberty away in the distance.
The first section of the High Line now ends at a wire fence at 20th Street.
The next 10 blocks should be open in a year or two and a battle is still under way to preserve the line's northern extremity, the old rail yard, which is an enticing prospect for developers.
All in all, it is a masterclass in urban renewal, a kind of "strip-prairie" through the heart of the urban jungle.
And it is a testament to what Robert Hammond and a dedicated band of campaigners were able to achieve to preserve and re-use a forgotten part of Manhattan's heritage.
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