88. United States of America

 

Located in remote Chaco Canyon National Monument, New Mexico, the Pueblo Bonito Ruin dates to the A.D. 900's. Pueblo Bonito  was once up to four stories high, contained 800 rooms, 32 kivas (round ceremonial chambers), and was costructed of more than a million dressed stones. The monument occupies 34 square miles and contains 13 major Anasazi ruins and hundreds of smaller once.