Land Surveying Incorporated

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Gillette, WY 82716

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Monoliths of The Wyoming-South Dakota Stateline


There are many interesting and historical survey markers that land surveyors come across while working in the field.  Among the most remarkable in our region are the 600 to 700-pound granite monoliths that are set along much of the state border between South Dakota and Wyoming.  Despite their age, most of these are still standing today.

These 6-foot tall stones were set in 1904-1905 by Edward F. Stahle and Frank S. Peck, one placed at nearly every mile marker along the boundary. Many of the granite posts were quarried in Sioux Falls, SD, hauled to Edgemont by train, and then carried by mule wagon to the appointed place.  The posts are marked with the mile marker number, the states, and the year they were installed.  See our article in the Lines & Points publication for more details and pictures of these markers:

Stahle and Peck were not the first surveyors to mark the state boundary.  It was originally surveyed and marked using cottonwood posts by Rollin J. Reeves in 1877.  Land surveying during this time in history was certainly no easy task, with travel by horseback through remote lands and the regular threat of Indian attack. Even as some surveyors requested a government military escort, survey groups were often attacked by Indian groups, resulting in the loss of survey instruments, equipment, and notes.  Imagine the skills of these early survey groups, as they had to blaze trails and peservere in remote and rough terrain, perform their work with precise survey measurements, all while keeping a vigilant eye out for possible threats.

Over time many people (not only land surveyors) have become interested in exploring and learning more about these monoliths along state borders.  The “Boundary Walker” Emmett Bennett, upon his retirement from the US Post office, walked the boundary of almost the entire state of South Dakota, except for the areas where the Big Sioux and Missouri Rivers provide a natural boundary.  He died at age 88 while trying to find the Initial Point of the Black Hills Meridian on the Wyoming border. We visited this point in 2019 and reflected on its history in our blog article here:

We are thankful that these days, we can work with the conveniences of modern GPS units and smart phones.  The biggest threats we face in the field today are adverse weather and rattlesnakes.  We are fortunate to occasionally have projects that allow us out in the field to document these pieces of history, as it gives us the opportunity to reflect on the historical aspects of land surveying.

Author info:  This article was a compilation of contributions from Troy, Cevin, and Jessica.


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