Flaming Geyser State Park preserves an unusual mining-era landscape along the Green River near Black Diamond in King County, Washington. Its name comes from a methane vent created when early 1900s test drilling for coal struck gas and saltwater, reportedly sending water and flames into the air; a nearby mud hole, the Bubbling Geyser, comes from the same underground source. Though the park’s namesake flame had gone out by 2016 after the methane was depleted, the site still reflects the area’s coal and cinnabar history. Once a private attraction, it later became state parkland and now combines this local curiosity with river recreation and conservation.