The Ross Trails Adena Circle is an archaeological site in the southwestern part of the U.S. state of Ohio.
Located northwest of Ross in Butler County,[2] it appears to have been a sacred circle constructed by people of the Adena culture.
Its interior, which is slightly raised above the surrounding terrain, can be accessed through a small opening in the wall that appears to have housed a gate at one time.
[3]: 103 In 1975, the circle's archaeological value was recognized when it was added to the National Register of Historic Places.
The landmarked area includes approximately 3 acres (1.2 ha) of land,[1] due to the possibility of finding related artifacts in the close vicinity of the circle.