BATON ROUGE, La. (BRPROUD) — LSU says new research shows that both LSU Campus Mounds are the oldest man-made structures in North America — going back as far as 11,000 years ago.

The two mounds on LSU’s campus stand about 20 feet tall and are among over 800 man-made mounds in the state, according to the university.

A study of the mounds says researchers believe that the mounds could have been used for ceremonial or cremation purposes. LSU said scientists are unsure what type of mammals were cremated or why.

Today, LSU has taken measures to protect the mounds with vehicle barriers, signage, temporary fencing, and rules discouraging people to walk on the mounds. There are also plans in the making by a committee to further protect the mounds through design to create a buffer between people and the structures.

The study was led by LSU’s Department of Geology & Geophysics Professor Emeritus Brooks Ellwood. Research of the campus mounds will be presented by Ellwood on Friday, Aug. 26. The presentation will be from 3:30 p.m. to 4:30 p.m. at Dalton Woods Auditorium in the LSU Energy, Coast & Environment Building (93 South Quad Drive).

For more information about the LSU Campus Mounds, click here.