In June 1867, Alexander Aiken, John Person, and Jonas Stough located a rich gold quartz lode near here, the name commemorating the recent laying to the second transatlantic telegraph cable.

Like many fabulously rich mining properties in Montana, this one was found by accident. Camped on nearby Flint Creek, the men's horses drifted off. In tracking them to this vicinity the men found not only good placer gold in Warm Springs Creek, but also promising gold quartz prospects on Cable Mountain. Within a short time, a small mining camp, called Cable City, grew up around the mines. In 1868, the Helena Weekly Herald found the miner "of this extraordinary camp … to be men of intelligence, of extended experience, good hard sense and big hearts."

The Atlantic Cable Mine operated with indifferent success until about 1880 when miners struck extremely rich ore dead under the mountain. A 500 ft. piece of ground produced over $151 million in 21st century dollars! Butte copper king William A. Clark paid $10,000 for one chunk of ore taken from this mine in 1889 and claimed it was the largest gold nugget ever found in Montana.

Erected by Montana Department of Transportation.