Little Island, Pier 55 at Hudson River Park, Hudson River Greenway, New York.

I've been lucky enough to visit so many cities and countries, but this is still my favorite place in the world. I don't think I've ever found another park with architecture quite like it. The way it's built over the river, the concrete "tulips," the winding paths, the different elevations, and how the gardens are worked into all of it make it feel completely unlike anywhere else. Malta is a close second tho.