During the summer of 2016, photographer Ethan Welty embarked on an odyssey through the northern Cascade Mountains in Washington State. His goal: to visit historic fire lookout structures and document the work volunteers are doing to maintain them. The lookouts were built by the United States Forest Service during the first half of the 20th century as places where rangers could spot wildfires before they spread. Most of them were decommissioned by the 1960s, but many are kept up by local groups and used as shelters for hikers and mountain climbers.

“I’ve become really interested in backcountry shelters in all their forms,” says Welty. “They are warm and welcoming, and create tiny, isolated communities that are very temporary.”

By staying overnight at each lookout on the following pages, Welty gave himself the chance to capture the lookouts under the stars and in the gray light of dawn. Most important, he got to know a few of the people who devote time and energy to the preservation of these fragile, improbably sited places.