Stretching from the east to the west gates of Glacier National Park,
Going-to-the-Sun Road, nearly 50 miles in length, took 11 years to be completed. With construction beginning in 1921, it was not until 1932 that the first car journeyed the complete route from the west gate of Glacier National Park to the east gate at St. Mary. It wasn't until the following year that, with both U.S. and Canadian dignitaries on hand,
Going-to-the-Sun Road was officially opened on July 15, 1933.
Passing through some of the most awesome and beautiful mountain scenery in the country as it climbs toward, then descends from, the Continental Divide, Going-to-the-Sun Road has become one of the Northwest's most popular back country mountain roads, as well as having been declared a Historic Civil Engineering Landmark.
FIRST - Major Trans-mountain Scenic Highway in the U.S.
When completed, the Going-to-the-Sun Road was the first major trans-mountain scenic highway in the United States.
Considered one of the world's most scenic mountain drives, the two-lane Going-To-The-Sun Road through Glacier National Park was the first major road to be constructed directly over high mountain terrain, proving that roads did not need to be limited to mountain passes.
Glacier National Park was established in 1910. At the time, the road system included several wagon paths on the west side of the park and a 35-mile rough road on the east. But it wasn't until 1917 that Stephen T. Mather, Director of the National Park Service, suggested the construction of a highway over the Continental Divide. Going-to-the-Sun Road connects the eastern and western portions of the park, providing vehicular access to areas that previously could only be reached by foot or horseback.
From ASCE
Going-to-the-Sun Road
Going-to-the-Sun Road, a trans-mountain road in Glacier National Park, Montana, extends from West Glacier at the park's western entrance to St. Mary on the eastern boundary. The nominated portion of the 48.7-mile-long road begins on the west side of the Continental Divide at the T-junction at the foot of Lake McDonald, beyond Logan Pass on the east side of the Continental Divide to Divide Creek on the eastern park boundary at St. Mary.
The road follows the east side of Lake McDonald up McDonald Creek Valley following McDonald Creek to the Loop, thence over Logan Pass, through the Hanging Gardens, then skirting the north side of St. Mary Lake to Divide Creek which is the eastern boundary of the park at that point.
On September 2, 1921, bids were opened for the first formal contracts for what would become the Going-to-the-Sun Road. In that year, the road grade was cleared for approximately 11 miles. By 1922, the road was completed as far as Lewis' Hotel. By 1924, the road was finished to the head of Lake McDonald and Avalanche Creek; the Mt. Cannon section was completed in 1925. Bids were opened each year and different contractors undertook the task of constructing sections of road. In 1925, the National Park Service and the Bureau of Public Roads reached an agreement whereby the Bureau became responsible for engineering and supervision of the construction work. Engineers conferred in Spokane, Washington, codified a procedural approach between the National Park Service and the Bureau, and decided to concentrate funding on the west side. Construction on the west side of the highway continued from 1925 to 1928 when the highway was completed as far as Logan Pass. Construction on the road was halted between 1929 and 1931 and was opened to tourist traffic the summer of 1929.
The National Park Service let contracts for the grading of the final link in the system. This tortuous stretch of road required the boring of tunnels as well as the grading of roads and clearing the right-of-way. As the project neared completion the Bureau of Public Roads also entered with a work force for maintenance activities. It is estimated that more than 60% of the excavation for the road was through solid rock and 1,919,689 cubic yards of material had to be moved. Twenty-two thousand, three hundred-seventy lineal feet of culvert pipe were laid. The west side tunnel contained 3,729 cubic yards of solid rock while the east side tunnel contained 6,778 cubic yards of solid rock. This amount had to be removed.
In 1932, the first car traveled over the Going-to-the-Sun Road. On July 15, 1933, U.S. and Canadian dignitaries officially opened the road.
From the NRHP Nomination Form