An interesting series of mound-like features off the coast of California.
 

An incredible series of ancient lines, circles and shapes has been documented similar to the famous landscape lines in Nazca, Peru except these lines exist on the American landscape.

Underwater, linear feature found in Cornwall, England.

Linear features approximately 6 feet wide visible around the coast line of Belize on the Yucatan peninsula.

A large, gridded topographic anomaly in the Atlantic Ocean seen with Google Earth.

This rectilinear feature has been spotted off the coast of NC, 22 miles SE of Harkers Island, North Carolina.

The circular feature is approximately 170 feet in diameter.

Circular features near Little Bighorn Basin in Wyoming.  The average diameter of the features is 35 feet.

Approximately 1.5 miles from the ancient city of Dimai an unusual mound site can be found.

The mounds can be found approximately 8 miles SE of Guyuan in Central China.