Trail Ridge Road
Crossing Rocky Mountain National Park with its highest point at 3,713 m, this is the highest continuously paved road in the United States. About 18 km of it runs through alpine tundra above the treeline.
Trail Ridge Road is the section of U.S. Route 34 that crosses Rocky Mountain National Park. It was completed in 1932. It runs from Estes Park in the east to Grand Lake in the west, about 77 km long, with its highest point at 3,713 m. It is the highest continuously paved road in the United States, and about 18 km of it lies above the treeline in alpine tundra. From east to west, the highlights are the elk meadows of Moraine Park and Horseshoe Park, the many-curved viewpoints, Rainbow Curve, the Forest Canyon Overlook, and Lava Cliffs. Near the summit is the Alpine Visitor Center (3,595 m), where you can walk tundra trails, and the Milner View overlook. The road then crosses the Continental Divide at Milner Pass and descends into the Kawuneeche Valley, where moose are common. It ends at Grand Lake. Driving without stopping takes about 2 hours, but a half day to a full day is recommended. The road usually opens in late May and closes in mid-October due to snow. From late May to mid-October, you need a timed entry pass during the day. The summit is 10 to 15°C colder than the base, and afternoon thunderstorms are common, so stay away from exposed ridges during lightning. Watch for altitude sickness and do not feed the animals. Old Fall River Road runs parallel to the main route as a one-way gravel road, and it is open in summer.