Why there are two ways over the divide here

At the far western edge of Clear Creek County, Interstate 70 meets the Continental Divide. There are two ways across, and knowing the difference helps on a mountain drive.

The fast way is the Eisenhower-Johnson Memorial Tunnel, which bores straight through the mountain. Before it opened, drivers had to climb up and over Loveland Pass on US Highway 6, a steep, winding route that gains a lot of elevation. The tunnel was built to spare travelers that climb and the weather that came with it.

The old pass did not disappear. Loveland Pass is still a paved highway, and it still matters. Some trucks carrying hazardous materials are generally kept out of the tunnel for safety and routed over the pass instead. That is why you may see big rigs grinding up Loveland Pass while most traffic slips through below.

For a resident or visitor, the practical points are simple. The tunnel is usually the easier crossing, but it can back up or meter traffic when it is busy. Loveland Pass is higher and more exposed, and winter storms can close it. In a bad storm, both routes can be affected at once.

Road status and any tunnel or pass restrictions change constantly, so this note does not quote live conditions. For the history and current rules, see CDOT, and check road conditions on the state’s COtrip site before you go.