The American highway that built its own national park

Countries & Cities · Published 3 October 2026 Swipe more like this →

In short: Most infrastructure projects aim to connect existing destinations, but Interstate 70 did something different in the desert. By carving a path through the San Rafael Swell, it created a stretch of road so desolate and unique that it may become the first national park born entirely from an engineering project.

The section of I-70 traversing the San Rafael Swell in Utah is a masterclass in isolation. Opened in 1970, this 108-mile stretch was the first highway in the United States to be constructed over an entirely new route since the Alaska Highway. At its debut, it held the distinction of being the longest segment of Interstate with zero services, offering travelers a raw experience of 'desolate beauty' through a geologic formation that was previously inaccessible by paved roads.

The engineering required to navigate this terrain is staggering. The route includes the Eisenhower Tunnel, which stands as the highest point in the entire Interstate Highway System at an elevation of 11,158 feet. It also features Glenwood Canyon in Colorado—the final piece of the original Interstate plan to open to traffic, completed in 1992. Because of the extreme geography, this section forced engineers to design corners sharper than standard Interstate regulations allow and required a speed limit of only 50 mph.

The legacy of I-70 is one of firsts and extremes. While Missouri and Kansas claim the honor of hosting the nation's first Interstate, I-70 serves as the 'Main Street of Kansas,' spanning the state's entire width. It even features a unique cultural footprint: the 'Alphabet Loop' in Kansas City, where exits are numbered 2 and suffixed with every letter except I, O, and Z. Today, the San Rafael Swell remains a candidate for national monument status, potentially making it a rare instance of a protected wilderness existing primarily because a highway paved the way.

Beyond its geographic feats, the road is woven into American sports history. The 1985 World Series was dubbed the 'I-70 Series' because the highway connects the two Missouri cities—Kansas City and St. Louis—passing within sight of both the Royals' and Cardinals' stadiums.

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