That's St. Maarten (SXM) in the Carribean.
Simply hundreds of photos like this of the place on airliners.net.
The threshold is literally the other side of the fence. There is high ground at the other end IIRC, just to add to the fun.
Anorak off, it's a bit warm today!
Edited to add caption "Heard there's some really top totty, we'll have a look on the way in"