A bag of corn chips dropped off a trail in Carlsbad Caverns National Park provided park staff with the perfect opportunity — albeit a disturbing one — to urge visitors to leave only footprints.

In the only U.S. national park with a roller-skating pavilion, Akiima Price strolls around the monthly Late Skate event making sure the community is happy. DJs provide the soundtrack as young skaters wobble in between adults with serious skills. Extended families watch from the sidelines. Vendors sell bubble tea and volunteers dole out apples and oranges. As always, skate rentals are free.

Photography has been a crucial part of volcano monitoring in Hawaii going back to the start of the USGS Hawaiian Volcano Observatory (HVO).

National Park Service staff at Bandelier National Monument in New Mexico on Friday were assessing damage caused by a flash flood that roared through Frijoles Canyon.