Holy Terror Mine

Legend says a Black Hills prospector named his richest strike after his own wife — not as a tribute, but as a joke about how often she had to drag him home from the saloon.

📍 Keystone, SD 📅 1894–1942 🏛️ Mine ⚖️ Closed

The Story

The Holy Terror Mine was discovered in 1894 by prospector William B. Franklin and his adopted daughter Cora at the base of Mount Aetna near Keystone. Its name comes from a well-worn local legend: Franklin had promised to name a big strike after his wife Jenny, but instead named it after her habit of hauling him home from saloon benders — reportedly musing, "Ain't she a holy terror?" Combined with the neighboring Keystone Mine, it became the largest gold producer in the southern Black Hills, helping push Keystone's population past 2,000 — briefly larger than Rapid City. It closed in 1903 (over lawsuits and water infiltration at 1,200 feet, not fire) and reopened for a final run from 1938 to 1942.

Surprising Facts

→ Franklin promised to name his big strike after his wife Jenny — then called it "Holy Terror" as a backhanded joke.

→ Combined with the Keystone Mine, it helped push Keystone's population briefly past Rapid City's.

→ Its 1903 closure came from lawsuits over miner deaths and water at 1,200 feet — not a fire or explosion.

Frequently Asked Questions

Where is Holy Terror Mine?
Holy Terror Mine is at Base of Mount Aetna (Keystone), Keystone, SD. Explore it on the When It Was interactive map.
How old is Holy Terror Mine?
Holy Terror Mine dates to 1894 and its story runs to 1942 — a span of 48 years.

More Black Hills History

Sources

https://www.keystonehistory.org/keystone-history