What's the highest point in Antarctica and how high above sea level is it?

Vinson Massif, elevation 16,066 ft. above sea level.

Highest plateau point is Dome A 4084 m. A dome is a high point on the polar plateau, a sort of massive dome of ice.

Dome C is 3233m and South Pole is 2,800 m

But the highest point is a mountain called Vinson Massif which is 4897m high (16,067ft)

check out the CIA factbook (online) >>

Elevation extremes:

lowest point: Bentley Subglacial Trench -2,555 m

highest point: Vinson Massif 4,897 m

note: the lowest known land point in Antarctica is hidden in the Bentley Subglacial Trench; at its surface is the deepest ice yet discovered and the world's lowest elevation not under seawater

not sure, but it might be the volcano Mt. Erebus