The Hudson-Meng Education and Research Center, in the Oglala National Grassland north of Crawford, covers a bonebed of about 600 extinct Bison antiquus roughly 10,000 years old, found in 1954 and listed on the National Register in 1973. In 2026 it opened on Fridays, 9 a.m. to 4 p.m. Mountain Time, from May 29 through Labor Day weekend, with tours of about 45 minutes booked on recreation.gov. The Bison Trail links it with Toadstool Geologic Park.