For centuries Native Americans came to these pure, flowing hot water springs for rest and healing, and legend holds that they called the area Peace Valley, laying down their weapons while they stayed because they believed the land and waters were for everyone to share and could not be owned. In the 1860s, prospector James Riley happened upon the springs and filed a land and water rights claim, and in 1864 he built a crude bathhouse and tavern. After Riley died of smallpox in 1882, new owners built a small, more fashionable hotel, which in 1891 was remodeled and enlarged in the Queen Anne style with fifty-two rooms, electricity, facilities for invalids, a resident physician, a gymnasium, and various entertainments. Between 1910 and 1913, the present bathhouse, east wing, and an addition at the west were built, and the older building was also remodeled with raised parapets and stucco to create a grand hotel in the California Mission style. Its opulent interior featured Tiffany glass lighting, beamed ceilings, and hand-stenciled walls in the Arts and Crafts tradition. Under various names and owners, Boulder Hot Springs served a wide range of guests and remains the last vestige of the many large-scale hot spring retreats that offered respite and recreation to early Montanans.