In 1889 railroad magnate Charles Arthur Broadwater opened his Hotel Broadwater and Natatorium west of Helena . The Natatorium was home to the world 's first indoor swimming pool . Damaged in the 1935 Helena earthquake , it closed in 1941 . The property ’s many buildings were demolished in 1976 . Today the Broadwater Fitness Center stands just west of the Hotel & Natatorium 's original location , complete with an outdoor pool heated by natural spring water running underneath it
1935 Helena earthquake
1935 Helena earthquake
Helena, Montana