Triangulation Station

1893 & 1925

Jerry Penry
April 17, 2010

Bear Butte is the location of the northern most triangulation station in the original 1893 U. S. Geological Survey network. Located to the northeast of Sturgis, South Dakota, it is an important landmark and a religious site for Native Americans. In 1961, the area was designated as a state park. Bear Butte is considered sacred to many Native Americans who make pilgrimages to leave prayer cloths and bundles tied to trees along the trails and at the top of the mountain. It is considered a place of prayer, meditation, and peace. The peak rises over 1,250 feet above the surrounding plain.

The mountain has undoubtedly had many notable visitors including Chiefs Red Cloud, Crazy Horse, and Sitting Bull. General Custer visited the area in 1874. Earlier in 1857, it was the site for a gathering of many Indian nations to discuss the growing presence of white settlers in the Black Hills.

In 1925, the U. S. Coast & Geodetic Survey established a second triangulation station to the west of the original USGS mark designated as "Bear". This newer marker was a bronze disk bolted to the top of a 3-inch diameter iron pipe. The 1893 station and the 1925 station were approximately 225' apart in an east-west direction.

The south side of Bear Butte.

The location of Bear Butte in relation to Sturgis, South Dakota.

Bear Butte as shown on the 7.5-minute U.S. Geological Survey quadrangle sheet. The triangle designates the location of the 1925 USC&GS triangulation station.

Oblique view of Bear Butte looking northeasterly. The red pushpin is the location of the original 1893 USGS triangulation station.

Looking north at the locations of the USC&GS 1925 bronze cap on iron pipe and the 1893 USGS chiseled "+".

The observation platform on top of Bear Butte at the 1925 triangulation station location.

Looking east from the observation platform toward the original 1893 triangulation station position.

This is the location where the adjusted latitude/longitude position took me. The original marker was described as being a chiseled "+" and lettered U.S.G.S. on a stone projecting 6" above the surface. Visitors to the top of Bear Butte have disrupted the stones in this area. A search was made for evidence of any markings on the stones, but it has most likley been destroyed a long time ago.

The location of the original USGS 1893 triangulation station. (Looking west toward the observation platform over the USC&GS 1925 bronze cap on iron pipe in the background).
The colored pieces of cloth are tied to the trees by Native Americans for religious purposes.

Looking east toward the location of the original USGS 1893 triangulation station.

Searching around the observation platform for the 1925 brass cap on iron pipe.

Success! The 1925 USC&GS marker still exists!

The side of the 1925 triangulation marker.

The cap of the brass cap on the iron pipe which is now hidden underneath the observation platform.
There was barely enough room for the camera to focus to get this photo.

Jerry Penry underneath the observation platform on the top of Bear Butte to get a photo of the 1925 capped iron pipe known as "Bear".

A view down the north slope of Bear Butte. The dead trees are a result of the devastating fire of 1996. The trees have never recovered on the mountain.

Looking south from atop Bear Butte toward the Black Hills. Bear Butte Lake is to the right.

This photo is believed to have been taken in the 1890's which was around the same time that the original USGS triangulation station was placed on Bear Butte in 1893. Fort Meade is in the foreground and was most likely a supply location for the surveyors of the U.S. Geological Survey.

Back to USGS Black Hills Triangulation

© Jerry Penry 2010