Kind of surprising.
I’ve done Flat Top Mountain two or three times. It’s 1000 ft less at 12,324 feet. But I’m a flatlander.
I’ll admit that once I got above the treeline I had to stop and rest about every 100-200 feet because the air is pretty thin up there. Never had elevation sickness though.
I’ve been to the top of Trail Ridge Rd in the Park-—no problems,but I wasn’t exercising——just walked around for a while.
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