NEW DELHI — Ed Dohring, a doctor from Arizona, had dreamed his whole life of reaching the top of Mount Everest. But when he summited a few days ago, he was shocked by what he saw.

Climbers were pushing and shoving to take selfies. The flat part of the summit, which he estimated at about the size of two Ping-Pong tables, was packed with 15 or 20 people. To get up there, he had to wait hours in a line, chest to chest, one puffy jacket after the next, on an icy, rocky ridge with a several-thousand foot drop.

He even had to step around the body of a woman who had just died.

“It was scary,” he said by telephone from Kathmandu, Nepal, where he was resting in a hotel room. “It was like a zoo.”

This has been one of the deadliest climbing seasons on Everest, with at least 11 deaths. And at least some seem to have been avoidable.