Oklahoma has a radical solution for repairing the state's busiest highway.

Tear it down. Build a park.

The aging Crosstown Expressway — an elevated 4.5-mile stretch of Interstate 40 — will be demolished in 2012. An old-fashioned boulevard and a mile-long park will be constructed in its place.

More than a dozen cities have proposals to remove highways from downtowns. Cleveland wants to remove a freeway that blocks its waterfront. Syracuse, N.Y., wants to rid itself of an interstate that cuts the city in half.

In the 1950s and '60s, mayors, governors and planners thought downtown highways would help keep cities alive by paving the way for suburban commuters to get in and out. Today, many of those same groups view downtown highways as a plague, wrecking neighborhoods, dividing cities and blocking waterfronts.

Some cities want traffic routed around downtowns. Others want tunnels or highways that pass under streets. A number of cities want to close highways and replace them with — nothing.