Topock Maze is located near Interstate 40 south of Needles, California.  It consists of a vast area of intricate parallel lines over the surface of the desert, estimated at 600 years old w/ its purpose unknown.  Some say that it was made from the native Mojave people long ago while another recent proposal has attributed the lines as railroad work in the 1880s, which in-turn has had issues of destroying other archaelogical sites.  Sections of this maze have been destroyed from the construction of nearby I-40 as well as other recent innovations.  Access here is limited via a small faint trail running through, the maze itself is protected & is on the national register of historic places.