La Gruta Hot Springs is 10 km (6 mi.) n. of San Miguel on Mex. 51, the road to Dolores Hidalgo, following signs. A hilly green oasis in the midst of a dry, dusty landscape, La Gruta (The Grotto) is one of the most popular of the region's several thermal hot springs.
The 12-acre, tree-shaded site is located just off the highway and has several interconnected pools, each with a lawn and table/chair area. One of the pools is underground, accessed by walking in a dim and narrow tunnel in about 4 feet of water; the tunnel leads to a domed cavern where a jet of warm spring water blasts from a pipe in the wall. The soothing water is non-chlorinated and has no sulfurous odor. Visitors also can indulge in a massage or spa treatment.
Changing rooms, restrooms, lockers and shower facilities are provided. Outdoor wooden stair access is on the rustic side. No outside food or beverages are permitted.