Lamb Spring Archaeological Preserve

A nonprofit organization

$2,804 raised by 13 donors

56% complete

$5,000 Goal

Lamb Spring is a unique and valuable resource for public education and research because the site contains what may be some of the best-preserved evidence of the earliest humans to live in the North American Continent, as well as the remains of many extinct Ice Age animals.


The Lamb Spring Archaeological Preserve (LSAP) is proud to promote the "Mammoth Site" of Hot Springs, South Dakota as a "sister site" to our own unique preserve. The Mammoth Site is an active paleontological dig, which boasts the largest concentration of mammoth remains in the world. Friends and colleagues at the Mammoth Site have been generous with their time and advice regarding the growth of our preserve. If you visit western South Dakota, please visit their site and be sure to leave a comment regarding your interest in both preserves!


To promote education, stewardship, and scientific research at the Lamb Spring Archaeological Preserve, through responsible conservation and development.

Background Statement

Mr. Charles Lamb, a Littleton, Colorado rancher on the South Platte River, excavated his spring in the summer of 1960 in order to develop a stock pond. A mammoth tusk and several bone fragments were visible on the banks of the spring just below the water's edge. As Mr. Lamb completed the stock pond, he observed several bone fragments in one of his dragline buckets. The bones were subsequently identified as Pleistocene mammal bones by Dr. G. Edward Lewis of the U.S. Geological Survey in Denver. Dr. Lewis visited the site and identified the remains of mammoth, horse, camel, bison, antilocaprid (pronghorn-Pliocene or Miocene), and several smaller mammals, mostly rodents (Wedel 1962). During the summer of 1960, Glenn Scott, a geologist for the U.S. Geological Survey joined Dr. Lewis and they attempted to determine the extent of the bone fragments around the spring. While doing hand auger tests, they uncovered several worked flint chips which suggested late Pleistocene human activity (Wedel, 1962).

There appeared to be a relationship between the artifacts and the faunal assemblages because they were both in the same type of sediment and recovered from relatively the same depth (Stanford, Wedel, and Scott 1981). Dr. C.L. Gazin, Curator of Vertebrate Paleontology, and Dr. Waldo R. Wedel, Curator of Archaeology form the Smithsonian Institution arrived to conduct excavations during 1961 and 1962. Major funding was provided by the National Science Foundation through a two year grant (NSF G17609). Dr. Gazin, Dr. Lewis, and C. Bertrand Schultz of the University of Nebraska State Museum, analyzed the vertebrate remains. Glenn Scott and Holmes Semken of the University of Michigan served as the project geologists, and Dr. Wedel and his field assistant, George Metcalf, carried out the actual excavations.

The excavation during 1961-62 under Scott and Wedel resulted in the identification of eight geological levels, or stratigraphic units, that have been interpreted to represent different events during the geological history of the site. Bones and artifacts were uncovered in these various geological units with the most abundant occurring in the lowest stratigraphic level, Unit 1, which is approximately 5-6 feet below the surface. Scott and Wedel hypothesized that Pleistocene peoples were responsible for the discharge and modification of the faunal (animal) remains found in Unit 1. The evidence supporting their hypothesis proved inconclusive and the project was terminated by the end of the summer of 1962 (Stanford, Wedel, and Scott 1981). A second bone bed was documented in Unit 2 and contained the skeletal remains of bison, eight Cody complex projectile points, a Cody complex knife, a scraper, a flake cutting implement, and several lithic (stone) flakes (Stanford and Fisher 1992). Two radiocarbon dates on bone collagen from Unit 2 are 6,870 +/-350 B.C.

Excavations were resumed at the site in 1980-81 by Dr. Dennis Stanford and Glenn Scott of the Smithsonian Institution. Dr. Russell Graham of the Illinois State Museum was the project's paleontologist, and Mr. Jim Rancier served as excavation coordinator. An early radiocarbon date of 11,140 +/- 1,000 B.C. run on bone by Wedel suggested to Stanford that the Pleistocene accepted archaeological evidence for humans in the Americas. Dr. Stanford terminated the excavation and backfilled the site following the 1981 field season (Stanford, Wedel, and Scott 1981, Stanford and Fisher, 1992).

The excavations, under the direction of Stanford during 1981-82, exposed an area of some 2,400 square feet immediately north of the spring vent. The primary focus of the excavations were the controversial Unit 1 bone bed. However, he also recovered bison bones and artifacts from Unit 2 further documenting the extensive Cody complex occupation at the site (Stanford and Fisher 1992; Stanford, Wedel, and Scott 1981). The evidence to support the fact that Lamb Spring is a Cody complex site is apparent from the character of the bison bone bed and stone artifacts that were recovered from the Smithsonian excavations. The 1981-82 collections excavated by the Smithsonian Institution are housed the National Museum of Natural History in Washington, D.C. The Cody complex component was the subject of a taphonomic and archaeological analysis that resulted in a master thesis at the University of Calgary, (Alberta, Canada) in 1984 (McCartney 1984).

In 1995, The Archaeological Conservancy, with help from the Denver Museum of Nature and Science, the Smithsonian Institution, and Douglas County, purchased the 35 acres containing Lamb Spring.

In partnership with the Smithsonian Institution, the Denver Museum of Nature and Science (DMNS), the University of Colorado-Boulder, Douglas County, and the Archaeological Conservancy, in July 2002, Dr. E. James Dixon, and Dr. Murphy supervised the excavation of a Columbian Mammoth skull. The mammoth skull was originally exposed, photographed, and reburied by the Smithsonian Institution in 1981, and was in need of professional conservation and preservation.

The excavation, removal, and transport of the skull took place in July 2002. Under the supervision of Drs. Dixon and Murphy, students and volunteers from the Museum Studies Program at the University of Colorado-Boulder and the Denver Museum of Nature and Science (DMNS) participated in the excavation of the skull. Once the skull was transported to DMNS it was exhibited, stabilized, and cast. The complete Colombian Mammoth skull was on display in the North Atrium of the DMNS from July 2002 until January 2003. Currently, it is in storage at the DMNS until there is an adequate storage facility at Lamb Spring.

Lamb Spring Archaeological Preserve (LSAP) began in 2006 as a group of interested stakeholders combined their talents to found an organization dedicated to careful stewardship and interpretation of the Lamb Spring archaeological site. A designated a 501(c)3 organization, LSAP works in concert with the landowner, The Archaeological Conservancy (TAC), a non-profit organization established in 1980 to acquire and preserve America's most important archaeological sites. With the support of the Scientific & Cultural Facilities District (SCFD), Douglas County, the Colorado Archaeological Society and many others, we are making steady progress towards Our Mission.

Organization Data


Organization name

Lamb Spring Archaeological Preserve

Year Established


Tax id (EIN)



Arts, Culture & Humanities


W. Titan Road
Littleton, CO 80125


8155 Piney River Ave Suite 200
Highlands Ranch, CO, CO 80129


8155 Piney River Ave Suite 200
Littleton, CO 80125

Service areas

Douglas County, CO, US





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