Out on a far section of Wendover Airfield, you’ll find what remains of the loading pits for the Silverplate B-29 Superfortress bombers. The size of the atomic bombs were such that they couldn’t be loaded in a traditional manner into the bombers because of their height. As such, the training bombs at Wendover (called pumpkin bombs which were the same dimensions and weight) were lowered into the pits. The bombers were then maneuvered over the pit, and the bomb was raised on a hydraulic jack into the bomber.
The full access tour at Historic Wendover Airbase (usually offered twice each year) takes visitors out to the bomb pits to see what remains. These same pits were replicated on Tinian for deployment during World War II and the culmination of the Manhattan Project.
Below is a video (no sound, courtesy the Atomic Heritage Foundation) showing the atomic bomb loading pits on Tinian along with the loading of Little Boy into Enola Gay and Fat Man into Bockscar.