If decisiveness isn’t your strength, you might want to avoid U.S. 36. Opened in 1951, the highway turned into a commuting nightmare as more people moved to Denver, Boulder, and everywhere in between. So in 2012, the Colorado Department of Transportation began work on a $497 million project to widen the roadway from four lanes to six. The first phase, from the Interlocken Loop to Federal Boulevard, will be done this summer, and many are calling it a national model because of the options it offers. The “express lanes” (one in each direction) are free for carpoolers, but singles can take them if they’re willing to pay the toll ($13.83 one way from Interlocken to Denver during peak travel times; $7.75 if you get an ExpressToll pass). Once phase two is complete in early 2016, a new bus service between Denver and Boulder—the Flatiron Flyer—will shave 20 minutes from the typical travel time. Also part of phase two: the 18-mile U.S. 36 Bikeway, for those who take their morning coffee with a serving or two of sweat.

(Read more about in-progress improvements for Denver roads)