"In the past fifty years, tens of thousands of miles of urban highways were built around the world. Many are now approaching functional obsolescence. This is leading many cities, not just in the United States, to question the place of major highways in urban areas and whether they merit further investment or should be removed. Today, some of the same urban highways that were built in that period are being torn down, buried at great expense, or changed into boulevards. (Quoted from paper)