Interstate 81 runs through the heart of Syracuse, N.Y., where a 1.4-mile-long elevated stretch of the highway is known locally as "the viaduct." Like many road projects built in the middle of the last century, I-81 is bumping up against the end of its life span. While officials say it's still safe to drive on, the highway is crumbling in parts.
Cities and cars share a conflicted relationship these days. Environmental concerns, growing traffic congestion and an urban design philosophy that favors foot traffic are driving many cities to try to reduce the number of cars on the road. In cities such as Seattle, Chicago, Toronto and Boston, some people go so far as to claim there is a "war on cars."