A friend owns some radio sites. If a tower starts with a pyramidal base, I can do 80 feet, easy. When it necks down to about 16”, it messes with my head, even though I know that the tower routinely gets subjected to 100+ mph winds. If I start on a 16” tower, it’s not a problem, but I think his towers that start at that size are only about 40 feet tall.
Yeah 40 ft seems doable, but I remember climbing the 40 ft tower to some kind of 12 ft high beam with a set of stairs in the middle that you walked in the slid down a cable at the end. I was white knuckled on the climb, but the beam was simple except for those stupid three steps up and down in the middle.