"The distance to the horizon in miles from height of an observer is approximately equal to 1.23 times the square root of the height in feet." - http://www.david

"The distance to the horizon in miles from height of an observer is approximately equal to 1.23 times the square root of the height in feet." - http://www.davidsenesac.com/Information/line_of_sight.html http://www.davidsenesac.com/Information/line_of_sight.html