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Kansas Geological Survey, Open-file Report 2008-14

Geologic Guideposts Along the Overland Trails in Kansas

by John Charlton and Dan Merriam
KGS Open-file Report 2008-14

Images for this presentation are available in an Acrobat PDF file (13 MB).


The California/Oregon and Santa Fe trails across Kansas were marked by natural recognizable features--geological guideposts. The trails generally followed topographic highs adjacent to rivers and in many instances were along well-marked Indian trails. The longest trail across Kansas was the Santa Fe which used the watering holes of Diamond Spring and Lost Spring as guideposts and prominent topographic features such as Pawnee Rock (Cretaceous Dakota Formation) in Pawnee County and Point of Rocks (Tertiary Ogallala Formation) in Morton County. The trail skirted Cheyenne Bottoms and followed the Arkansas River from the Great Bend to the Colorado border unless the dry route was taken from the Cimarron Crossing. On the California/Oregon trail Alcove Spring in Marshall County was a noted feature as was Blue Mound (Pennsylvanian Oread Formation) in Douglas County. River crossings were another feature marking location on the trails as the Blue Jacket crossing over the Wakarusa near Lawrence. The Cimarron crossing of the Arkansas River on the short route to Santa Fe was a guidepost on that route. River crossings were usually where the water was lower and the river bottom was firm. Topography and geology were the guide for location of the trails, thus played a major role in location of these early trails across the great American interior.


The overland trails from West Port Landing (Kansas City) to Oregon/California and Santa Fe crossed Kansas starting in the mid-1800s. The crossing was by foot, horseback, or wagon and was an arduous undertaking. Many who started on the adventure did not arrive at their destination. In addition to weather and trail conditions, there were pestilence, and disease.

The trails generally followed the earlier Indian trails which had followed animal trails. They stayed high topographically so there was an unobstructed view of the country, and it was drier and generally easier going. At the end of a day, camp sites would be along a river or at a spring and where firewood was available for cooking and warmth. If the weather was too cold or too hot, there were problems with the draft animals and travelers. Frequent snow storms in the winter and rain torrents in the summer created problems. River crossings could be dangerous depending on the weather and water level. In short, it was not an easy venture.

Nevertheless hundreds of pioneers made the trek for one reason or another. Many seeking a better life, others seeking fortune. If fatigue set in or the travelers found a place to their liking along the way, they would put down roots and stay; some did so in Kansas. Today the trails are marked by trail markers. Highway US56 essentially follows the old Santa Fe trail, but the Oregon/California trail cut obliquely across northeastern Kansas.

Geology Background

The trails start in the Missouri River bottoms and proceeded westward across the Osage Cuestas in eastern Kansas. Near present-day Gardner the trails split with Santa Fe continuing west and the Oregon/California trail heading northwest.

The Oregon/California trail crossed the Pennsylvanian rock units of the Osage Cuesta country and skirted or passed through the glaciated area of northeastern Kansas to the Nebraska state line. The Santa Fe trail from east to west crossed younger and younger geological units ranging in age from Pennsylvanian rocks in the east (Osage Cuesta country), through the Flint Hills to the Cretaceous units in the Smoky Hills to the Tertiary sediments forming the High Plains.

The longer Santa Fe trail crossed a series of steps that are formed in the Upper Pennsylvanian rock units by the alternating low west-dipping hard limestone beds underlain by softer, easily eroded shale, so that the steep face is to the east forming a cuesta. Going from east to west is like leafing through a book from back to front as the older geologic units are in the eastern part of the state. So, the trail crossed the cuesta country until reaching the Flint Hills.

The Flint Hills are composed of thicker chert (SiO2)-bearing limestones that form an extensive grassy region trending northeast across the state. Because of the hardness of the weathered out chert from the Lower Permian limestones, the region is not farmed except in the lowlands adjacent to river and creek bottoms. Here, was located the Last-Chance Store and the treaty tree near present-day Council Grove. Council Grove also was a postal drop and too the less hearty turned back and the adventuresome souls continued west. Once this region of prairie grass was crossed, the trail followed the softer Middle Permian shales to the Cretaceous beds as exposed near Salina, Lindsborg, and McPherson. The harder Cretaceous rock units overlying the softer Permian shales form a topographic barrier with features such as Coronado Heights near Lindsborg in Saline County.

The Cretaceous was skirted to the south continuing west just south of Cheyenne Bottoms to the great bend in the Arkansas River near present-day Great Bend in Barton County. Following the river--there was a high road on the High Plains for wet weather and a low road for dry weather in the Arkansas River Lowlands. The trail followed the Arkansas River for many miles to the Cimarron Crossing in Gray County and then crossed the High Plains on the dry route or continued west along the river route.

Topographic Guideposts

Prominent topographic features, reflecting the geology, were natural guideposts along the trails. After the trails were established, they provided location mile markers for the travelers. None of the better known topographic features in Kansas, Monument Rocks, Castle Rock, Mushroom Rock, and Coronado Heights, however, were on these trails.

The guideposts on the Oregon Trail were the river crossings and the springs. The Blue Jacket and Blanton crossings near Eudora in Douglas County were the best known and perhaps the Kaw River crossing near Topeka was more arduous. Before surmounting Mt. Oread in Douglas County, a prominent cuesta formed by the Upper Pennsylvanian Oread Limestone, Blue Mound, also capped by the Oread Limestone, was a recognizable topographic feature for the travelers in the Wakarusa River valley.

The trail had stops at Scott Spring at the Rock Creek crossing near Westmoreland in Pottawatomie County and Alcove Spring just north of Blue Rapids in Marshall County, which was a favorite camping spot. Alcove Spring was the best known feature on the trail in Kansas on the way to the Platte River Valley in Nebraska.

Guideposts on the Santa Fe Trail were numerous and included several well-known frequented springs. Springs were likely places for rest and camping and the travelers on the trails took advantage of their presence. Diamond Spring in Morris County, Lost Spring in Marion County, Wagon Bed Spring on the Cimarron River in southern Grant County were well known.

In the western part of the state, the Arkansas River was followed from the great bend. Pawnee Rock (Cretaceous Dakota sandstone) in Barton County was a noted guidepost. Kit Carson once camped here.

Likewise river crossings were good markers. The Cimarron Crossing was a decision point--continue on westward following the river or take the shortcut across the dry High Plains. The dry route crossed the Cimarron River at Wagon Bed Springs and on to the prominent Point of Rocks before continuing on across country to Santa Fe.


The topographic guideposts were recognizable markers along the trails. The guideposts gave the travelers a sense of and the satisfaction of progress on their journey.

Related References

Merriam, D.F., Hambleton, W.W., and Charlton, J.R., 2005, Kansas artistic geologists and illustrators: Kansas Geol. Survey, Open-file Rept. 2005-33.

Merriam, D.F., Charlton, J.R., and Hambleton, W.W., 2006, Kansas geology as landscape art: interpretation of geology from artistic works: Kansas Geol. Survey, Open-file Rept. 2006-11.

Merriam, D.F., and Charlton, J.R., 2007, Artists and illustrators along the Kansas overland trails: geology from their pictorial records: Kansas Geol. Survey, Open-file Rept. 2007-18.

Kansas Geological Survey, Geology
Placed online Oct. 3, 2008
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