Keystone in Pennington County, South Dakota — The American Midwest (Upper Plains)

Hayes-Hopkins Supply Company

Photographed by William Fischer, Jr., September 21, 2026

1. Hayes-Hopkins Supply Company Marker

Inscription.

John M. Hayes and his brother Patrick F. Hayes were millwrights. After completing the construction of the mill for the Harney Peak Tin Mining, Milling, and Manufacturing Company (Harney Peak Tin Company for short) at the top of Tin Mill Hill they moved to Keystone in 1894. This was shortly after the location of the Holy Terror Mine on June 28, 1894. The Hayes brothers were both single and they roomed and boarded at the Franklin Hotel. Recognizing the potential of a booming mining town they were soon in business at this location in a double wide, single story building. On the north side they sold, hardware, mine and mill supplies, boots and shoes, hats and caps, and clothing. In the other half of the store they sold groceries. They called their business Hayes and Hayes. Sometime later they took in their brother-in-law James G Hopkins, who had married their sister and had been the chief amalgamator at the Holy Terror Mill. They called their business Hayes-Hopkins Supply Company. The store supported three families.

[Photo captions, left to right, read]
• A winter scene in front of the Hayes and Hayes Store.

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• Main Street Keystone 1907

Erected 2005 by Keystone Area Historical Society. (Marker Number 5.)

Topics. This historical marker is listed in these topic lists: Industry & Commerce • Settlements & Settlers. A significant historical date for this entry is June 28, 1894.

Location. 43° 53.717′ N, 103° 25.105′ W. Marker is in Keystone, South Dakota, in Pennington County. It is on 1st Street (State Highway 40) just north of Blair Street, on the right when traveling north. Touch for map. Marker is at or near this postal address: 318 1st Street, Keystone SD 57751, United States of America. Touch for directions.

Regionally, this marker is in West River,

in the Badlands,

and in Greater Rapid City.

It is also in the American Black Hills,

in the Lewis & Clark Corridor,

on the prairies,

and on the Northern Plains.

Globally, it is in North America,

the Western Hemisphere,

the Western World,

and the Anglosphere.

Historically, it finds itself in what was once Rupert’s Land

and also the Louisiana Purchase.

Other nearby markers. At least 8 other markers are within walking distance of this marker: William and Jennie Franklin (within shouting

Photographed by William Fischer, Jr., September 21, 2026

2. Hayes-Hopkins Supply Company Marker

distance of this marker); Site of the McDonald Hotel (within shouting distance of this marker); Charles Upham and the Upham Saloon (within shouting distance of this marker); Tom Hoy and the Hoy Drug Store (within shouting distance of this marker); Big Thunder Gold Mine (within shouting distance of this marker); US Forest Service Icehouse (within shouting distance of this marker); Medical Office of Eugene B. Hultz, M.D. (about 400 feet away, measured in a direct line); Keystone Battle Creek Cultural Center (about 400 feet away). Touch for a list and map of all markers in Keystone.

Also see . . . Historic Keystone Walking Tour. (Submitted on October 3, 2026, by William Fischer, Jr. of Reynoldsburg, Ohio.)

Credits. This page was last revised on October 3, 2026. It was originally submitted on October 3, 2026, by William Fischer, Jr. of Reynoldsburg, Ohio. This page has been viewed 3 times since then. Photos: 1, 2. submitted on October 3, 2026, by William Fischer, Jr. of Reynoldsburg, Ohio.