A crater of unknown origins is located in the sandy grasslands on the north side of the national park. Access it by hiking off-trail about 1/4 mile (0.3km) northwest of the Liberty Gate Trailhead:
For many decades, research has sporadically occurred by different groups, with inconclusive results. In the 1960s, the Smithsonian studied the crater, concluding it was a windblown sand feature now covered by grass. However, the park geologist has ruled out it being formed from wind, because it has an even ejection rim around its perimeter.
Another theory is that the crater is a 'sand boil', formed as watery sand deposits are squeezed and pushed up along a fault line.
Last updated: March 14, 2020