How Far Away Is The Horizon?

Question

If you are around 6 foot tall, standing on even ground, completely flat ground, looking onto the horizon with nothing in the way. How far away is this horizon (or how far away is the furthest we can see without binoculars essentially)

Answer 1

For eyes 6' above flat ground (a person 6' 6" tall), the horizon is about 3.3 miles away. Binoculars make no difference because the limit is imposed by the curvature of the earth's surface. Ships had crow's nests in "the olden days" to extend the range of vision by getting higher up. For instance, eyes at 30' can see about 7.4 miles.

Answer 2

The horizon is 3.1 miles if you are 6 feet tall.

From this formula, your eyes are about 5.5 feet above the surface.

SquareRoot(5.5 / 0.5736) = 3.1 miles

Answer 3

A 6 ft. person standing on flat ground can see the horizon at a distance of about 22 miles.