Hristo Prodanov, Bulgarian engineer and mountaineer (born 1943)

Hristo Ivanov Prodanov, also known as Christo Prodanov was a Bulgarian mountaineer. Prodanov was the first Bulgarian to climb Mount Everest, doing it via the most difficult way—the West Ridge—as well as alone and without oxygen. Prodanov was the first person to climb Everest in April, when the weather conditions are generally too bad for an expedition, and also the thirteenth person to climb Everest without using bottled oxygen. Climbing the summit at 18:15 local time, he had to descend overnight and got lost shortly after that. On the next afternoon, he reported he had lost his gloves and soon would be unable to hold the radio button long enough to talk. His body was never found.