Rainbow Curve, 12.8 miles from the Beaver Meadows park entrance, lies on the outside edge of a wide switchback on Trail Ridge Road as it swings around a blunt ridge between Hidden Valley and Hanging Valley. This major viewpoint at 10,829 feet is just below timberline, the transition zone between a subalpine fir and spruce forest and the alpine tundra of grass and delicate wildflowers. The vista looks down on Horseshoe Park, an open grassy valley floored by twisting Fall River. Note the light-colored alluvial fan on the north side of the park. It formed in 1982 when Lawn Lake, a small reservoir in the Mummy Range, broke after heavy rain. A deluge of water, boulders, and debris swept down into the valley.
- A 32-space parking lot and toilets are alongside the road at Rainbow Curve, and a low stone wall encloses the entire overlook and parking area. You need to access the overlook when driving up Trail Ridge Road, since if you are descending it you can’t cross a double yellow line into the parking area. The road and overlook is usually open from May through October, depending on weather.
- Pay attention to the weather at Rainbow Curve Overlook as well as the viewpoints higher on Trail Ridge Road. Heavy thunderstorms accompanied by lightning quickly move across the area on summer afternoons, creating dangerous situations for sightseers. In July 2014, two people were killed in two days in separate lightning strikes on the road. A strike at Rainbow Curve Overlook killed one man and injured 13 others, while a woman died from a lightning strike the following day on Ute Crossing Trail above Rainbow Curve.
- Trail Ridge Road, the highest through highway in the United States, travels 45 miles over Trail Ridge in Rocky Mountain National Park. The road runs above 12,000 feet for four miles and over 11,000 feet for 11 miles. It climbs almost 5,000 vertical feet from Estes Park to its high point, traveling through three life zones, which is like traveling from Colorado to the Arctic Circle. The high grassy ridge has a severe climate with a short summer and over 40 inches of annual precipitation.
- After checking out Rainbow Curve, continue up Trail Ridge Road for more overlooks. Forest Canyon Overlook views deep Forest Canyon and the Continental Divide. Rock Cut Overlook, two miles north of Forest Canyon Overlook, has views of the Continental Divide and Longs Peak. Gore Range Overlook has views of the distant Gore Range and the Never Summer Range. Milner Pass lies below Fall River Pass and Farview Curve Overlook gazes down the Kawuneeche Valley on the park’s west side.
Recommended season(s): May through October.
—Stewart M. Green