New footbridge recently opened in Madrid; Parasela de Arganzuela in Spanish. Designed by French architect Dominique Perrault. It connects two parts of a new urban park on the banks of the the Manzaranes River. This space was formerly occupied by the M30 Expressway, which has been buried 25 meters (80 feet) below the surface, and some industrial spaces.
Below is a rendering of what the park is supposed to look like in a few years. More proof, I would say, that expressways are a terrible way to use space inside a city.