The road? Trail Ridge Road.
Topping out at 12,183 feet and crossing the Continental Divide at 10,758 feet, this road offers sweeping views of the mountains, tundra, high-alpine lakes, wildflowers, elk, mountain goats and marmots along its path.
Snow fields and gorgeous tundra along Trail Ridge Road — Photo courtesy of Hope Gately
From Boulder, you'll follow the dramatic twists and turns of Boulder Canyon to Nederland, Colo.
Along the way, expect to see rock climbers dangling precariously from sheer vertical rock walls; fly fisherman trying their luck in the pristine waters of the canyon's creek; and, during the spring and summer months, kayakers and rafters shooting the rapids.
As you pass through Nederland, keep an eye out for Eldora Ski Resort perched high above the town, and stop along the way for brunch with a view at Sundance Cafe.
Continue on your way to Peak-to-Peak Highway, where views are aplenty in all directions. CO-7 will sweep you down to well-known Estes Park, where you can take in a bit of history and mystery at The Stanley Hotel, known for its paranormal activity and as the birthplace of author Stephen King's The Shining.
Just beyond Estes Park's charming downtown, you'll enter Rocky Mountain National Park and follow the signs for Trail Ridge Road.
Though it's only an hour from Boulder to the road itself, the road covers 48 miles stretching between Estes Park and Grand Lake. It can take anywhere between one to two hours to drive its length, depending on how many stops you take for photos and exploration.
First called the "scenic wonder road of the world" by Rocky Mountain National Park, Trail Ridge is a designated "All American Road," and it's the highest continuous paved stretch of highway in the United States.
Construction for Trail Ridge Road began in 1929 and was completed in 1938. The road follows a path known, at the time, by Arapahoe Indians as the "Dog Trail." This ancient route was traversed by Native Americans to access hunting in the east, and it was typically marked by stone cairns.
Because Trail Ridge tops out at over 12,000 feet, it's important to keep in mind that the weather changes suddenly at these high altitudes. It's not uncommon for a bluebird day to go from sunny to dark and ominous within minutes.
Hail, thunder and lightning storms are regular occurrences during the summer months, so pay close attention to the weather and take shelter when necessary.