Yermo is a town in the Mojave Desert in San Bernardino County, California. Its name is derived from one of the Spanish words for "desert". It is 13 miles east of Barstow on Interstate 15, just south of the Calico Mountains. In 2009, the town's population was an estimated 1,750.Founded in 1902 and originally named Otis, the town is situated at a division point of the Union Pacific Railroad line. A post office was established three years later with William J. Flavin serving as Yermo's first postmaster. The town later developed around serving motorists traveling on the Arrowhead Trail, which ran through the community. Today, Yermo is governed by an elected five-member board of directors comprising the Community Services District authorized by the County of San Bernardino. The board, which meets monthly, oversees the town's volunteer fire department, the Yermo/Calico VFD, as well as its street lighting, parks and water system.