About 3 million years ago as the Rocky Mountains rose from the surrounding plains, a small rivulet that would become the Arkansas River rose with them. Over the millennia, it cut a deep channel for itself through the surrounding granite, at a rate of about one foot every 2500 years. The gorge's peculiar shape, contrasted to broad canyons such as the Grand Canyon, can be attributed to this long, direct erosion through hard rock.
Before European settlement, Native Americans of the Ute people wintered in Royal Gorge for its protection from wind and relatively mild climate. The Comanche, Kiowa, Sioux, and Cheyenne used Royal Gorge on buffalo hunting expeditions as an access point to mountain meadow regions such as South Park Basin.
Colorado's Rocky Mountain region fell under Spanish claims, and conquistador expeditions of the 17th century or fur traders may have seen Royal Gorge in their traversal of the area. The first recorded instance of a European arrival, however, is the Pike expedition of 1806. Zebulon Pike's group built a crude shelter in the gorge and explored the area, descending on horseback over the frozen Arkansas.
Nearby Caņon City was founded in 1860 to exploit possible mineral deposits in the area. Discovery of silver and lead near Leadville in 1877 prompted a race to build rail access to the area. The consequent Royal Gorge Railroad War between crews of the Santa Fe Railroad and the Denver & Rio Grande. Royal Gorge was a bottleneck along the Arkansas too narrow for both rail lines to go through, with no other reasonable access to the South Park area. The Royal Gorge War ended after two years of low-level guerrilla warfare between the two companies after Federal intervention prompted the so-called Treaty of Boston. The D&RG completed its line and leased it for use by the Santa Fe.
In the 1890s Royal Gorge was used as a passenger route for transcontinental rail travel. Four trains per day went through the gorge. Alternate routes through the mountains made Royal Gorge fall from favor for transcontinental use, and passenger trains on the main line stopped in 1967. A sightseeing train now follows the route through the gorge.
In 1929 Caņon City authorized the building of the Royal Gorge Bridge, which at 1,053 feet above the river is the highest suspension bridge over water in the world. The bridge forms the kernel of Royal Gorge Park, a theme park owned and run by the city. Other activities in Royal Gorge area include whitewater rafting and rock climbing.