Located in Butte, Montana, the Granite Mountain Speculator Mine Memorial is dedicated to the 168 miners who lost their lives in the worst disaster in hard rock mining history, which took place on June 8, 1917. The site is an open air plaza, with view of the Highland Mountains, the Continental Divide, and remains of Butte's mining industry. Interpretive signs are also on display describing the accident and the local mining and labor history.
The memorial opened in 1996 as a result of the work of Gerry Walter, a VISTA volunteer who was assigned to work in Butte. She studied the mining history of the city and discovered that plans for a memorial were started in 1917 but were never materialized. She led an effort to build the memorial dedicated to the miners who perished. The site was rededicated in 2010 after new features were added.