At the end of a dirt road in the Jemez Mountains lies a natural wonder that hints at the region’s fiery past. Known as Sulphur Springs, it lives up to its name, as the distinctive rotten eggs stench of brimstone wafts from the area. The site has geologic features like mud pots and fumaroles that are rare in the United States, and unique in New Mexico. There are also a few man-made creations—rusted-out cars, decaying cabins, and collapsing wooden fences. Sulphur Springs was first claimed in 1898 by Maríano Otero,…