^^^San Francisco is the best example of this (its double-decker elevated freeways were damaged in the '89 earthquake and it was a bit of a forced wise decision), but Seattle, Syracuse, and Milwaukee are also good, current examples.
In San Francisco's case, the Embarcadero Freeway cut the city off from the waterfront and elevated crime along the wharves. The waterfront everyone thinks of today with the Ferry Building, cruise terminal, Bloomberg offices, activated piers, Exploratorium, etc would not be possible if the freeway were still there. There are a series of leftover above grade walkways too that connect some of the area buildings above what used to be freeway offramps into the city.
The Central Freeway was closed down and removed to the chagrin of residents who used it to gain access to the interstate. However, what was once a neighborhood as infamous and dangerous as the nationally infamous Tenderloin is now my personal favorite neighborhood in the city and one of my favorite neighborhoods anywhere (I can't afford it, but I like to go). It's known as Hayes Valley and is absurdly cute and chic today - pictures do not do it justice and the vibe is unreal.
http://www.pps.org/reference/octavia-boulevard-creating-a-vibrant-neighborhood-from-a-former-freeway/http://www.cnu.org/highways/sfoctaviaThere's definitely precedence. Models would be found in other cities. I'll try to dig up better articles/pictures on the conversion of double-decker Central Freeway to Patricia's Green. On the road, however...