Taking the 500 meter height as the distance to the top rung, and dividing by the number of rungs that I counted (83 rungs), I got a distance of 6 meters or 20 feet between each rung. This is assuming that the ladders rungs are equally spaced, for ease of climbing.
Also, the distance between the rungs looks pretty similar to the distance between the side rails, so each rung is probably about 6 meters or 20 feet long.
In short, this is a Sky Ladder, for Sky Giants.
