How do we measure the height of mountains?

Question

I don’t think there is a measuring tape long enough…

In: 3

Answer 1

I’m pretty sure they measure it in relation to sea level. As in so many feet above sea level (for US). I’m assuming they use like air pressure or something similar to measure it.

Edit: did some quick googling and found out that barometric pressure is indeed how most altimeters work, but there are GPS altimeters that measure height by triangulating from different satellites.