The Mass Extinction Crag is a unique geological formation located in the Las Vegas Wash watershed of Nevada. It is a popular destination for scientists and geology enthusiasts, as it is one of the few locations in the world where one can observe evidence of the Permian-Triassic extinction event, which wiped out over 90% of all marine species and 70% of terrestrial species. The Crag consists of layers of rock that were deposited during this event, and contains fossils of various species that died out during the extinction. Visitors to the site can observe these fossils and learn about the conditions that led to the mass extinction, which is considered one of the most catastrophic events in the history of life on Earth.

In addition to its scientific significance, the Mass Extinction Crag is also a popular destination for outdoor enthusiasts and hikers. The area surrounding the Crag is home to a variety of wildlife, including bighorn sheep, desert tortoises, and various bird species. Hiking trails wind through the surrounding hills, offering scenic views of the Mojave Desert landscape. Visitors can also participate in guided tours of the Crag, led by experienced geologists who can provide in-depth information on the site's geological history. Overall, the Mass Extinction Crag offers a unique and educational experience for visitors interested in geology, paleontology, and outdoor recreation.