The Stratobowl: How Rapid City Launched Humans to the Edge of Space
One of the most extraordinary chapters in Rapid City’s history did not happen downtown or on a battlefield. It happened in a quiet, bowl-shaped valley in the Black Hills, where humans first rose to the edge of space.
A natural launch pad
Southwest of Rapid City, the land dips into a deep, sheltered hollow ringed by cliffs. In the 1930s, planners realized this natural amphitheater was a good place to inflate and launch an enormous balloon, because the high walls blocked the wind that could shred delicate balloon fabric. They named it the Stratobowl, the “stratosphere bowl.”
At the time, the stratosphere was the new frontier. Aviators in airplanes could not reach it, but a balloon filled with lighter-than-air gas could float a sealed gondola miles above the earth, provided it did not burst first.
Explorer I and the 1934 attempt
In 1934, the U.S. Army Air Corps and the National Geographic Society launched Explorer I from the Stratobowl. The flight climbed high into the stratosphere, but the giant balloon tore apart during descent. The crew bailed out by parachute and survived, a near-disaster that taught hard lessons for the next attempt.
Explorer II breaks the record
On November 11, 1935, the team tried again with Explorer II, this time using non-flammable helium instead of hydrogen. Captains Albert Stevens and Orvil Anderson climbed into a sealed metal gondola, and the balloon, one of the largest ever built at the time, lifted out of the Stratobowl before a crowd of spectators.
Explorer II rose to roughly 72,000 feet, about 13.7 miles above the earth, a world altitude record that would stand for more than twenty years. From that height the crew could see the curvature of the earth and the dark sky above the atmosphere. They carried scientific instruments aloft, gathering data on cosmic rays, the composition of the upper atmosphere, and the living organisms that could survive there.
After hours aloft, the balloon descended safely and landed on the plains of South Dakota. The flight was a national sensation, proof that careful engineering could carry people to the threshold of space, and a direct ancestor of the high-altitude and spaceflight programs that followed.
A quiet landmark today
The Stratobowl never became a tourist destination on the scale of Mount Rushmore or Dinosaur Park, but its place in history is secure. A hiking trail leads to an overlook above the bowl, where a visitor can stand on the rim and imagine a balloon taller than a skyscraper rising silently toward the stratosphere.
For a city that would later become home to Ellsworth Air Force Base, there is a fitting symmetry in the fact that Rapid City’s connection to flight reaches all the way to the edge of space, and that it began in a sheltered valley in the Black Hills.