- One of MT’s original nine counties, named for James Madison, then Secretary of the Treasury (later President).
- Virginia City, founded in 1865, is the county seat, founded in 1865. In 2017, the population was about 8,200. When it was a major site during the mining boom of the 1860s and 1870s, residents numbered app. 10,000. Gold, silver, copper, lead, coal, and later oil were dug; the richest area of placer diggings was in Alder Gulch, which became the site of Virginia City. Thousands of tourists visit this living history museum nowadays, largely thanks to the efforts of Charles and Sue Bovey who had begun buying up the town in the 1940s.
- During the 1860s and ‘70s, the stage route called the Vigilante Trail ran from Alder Gulch down the Ruby River to Twin Bridges and beyond.
- It includes Montana’s most famous trout streams and rivers: Madison, Jefferson, Big Hole, Beaverhead, Ruby. The Ruby River is a headwater of the Missouri River.
- Sacajawea’s statue stands in front of the Madison County Fairgrounds in Twin Bridges. Her fame precedes the Lewis & Clark expedition. Five years earlier she had been kidnapped by the Hidatsa and then purchased by Charbonneau. The Corps stopped at Beaver’s Head, her family’s summer camp, and sought help from the Shoshones. The Great Chief of the Shoshones turned out to be the brother of Sacajawea.
- The jewels of the Madison County Fairgrounds are the buildings—crafted by the Works Progress Administration in the 1930s. Tosten Stenberg, known for his log structures in Yellowstone Park, directed construction.
- Key towns are: Ennis, Sheridan, Twin Bridges, Virginia City, Nevada City, Harrison, Pony, Alder, Big Sky. Big Sky is a premier resort destination for the West. While many towns see schools and businesses close, they attract retirees. Each town, which offers something different, is well worth your time
- 109,000 acres are classified as prime farmland. 164,700 acres are subdivided; conservation easements put on 302,000 acres. Farming, ranching, tourism, several large construction companies are major employers. Non-traditional ranch property owners are becoming more common. Family ranches, livestock numbers, and lack of successful main street businesses are being threatened by high land values.
- In 1959, the famous Hebgen Lake earthquake caused major damage. The shock was felt a hundred miles away.
Madison County lies east of Interstate 15 and south of I90. The towns are served by US 287 which connects Twin Bridges with Ennis, passing through Sheridan, Laurin, Alder, Virginia and Nevada City; and Montana 41, which connects Twin Bridges with Dillon. Guest ranches, museums, and antique centers abound.