Appropriately enough for a gambling mecca, Las Vegas is taking a double-down approach to urban revitalization: Instead of rehabbing its existing downtown, it’s building a sparkling-new replacement, right next door.

[T]he city will formally inaugurate a new urban core on a 61-acre, undeveloped parcel of land — a project that some experts say is unprecedented in city planning. Called Union Park, its supporters hope it will revive the historic downtown just to the east, where the region’s courthouses, government offices and oldest casinos are clustered…

“It’s quite unusual that there’s a big swath of downtown ground just sitting there without having to go through a whole rigmarole to acquire,” said Bill Hudnut, a senior fellow at the Urban Land Institute in Washington. Mr. Hudnut, the former mayor of Indianapolis, recalled that acquiring just three blocks of that city “involved some legal fights and eminent domain, the demolition of buildings, numerous deals with numerous owners.” In Las Vegas, he added, “they’re just building new stuff.”

And I suppose if Union Park fizzles out after it goes up, they can just pick up another several adjacent acres and take a third stab at it. All that desert terrain is just a blank slate anyway, right?