How about the top of Mt Everest or Mt McKinley? Or is that not enough to matter?
Too cold......................
How about the top of Mt Everest or Mt McKinley?
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Are there roads and utilities going to the tops of those mountains?
If you could get Pele's and Poli'ahu's buy-in, Mauna Kea.
It's near the equator, so you get the best boost from Earth's rotation, at 13,803 ft above sea level, it is the highest point in the state of Hawai'i, so it's above the thickest part of the atmosphere. Plenty of open water for boosters (or failed launch debris) to splash down in in all directions, ability to launch polar orbits and a nice slope for a rail based launch to boot. And it's uncontested US territory.