National Historic Landmark

Research Cave

Portland, Callaway County, Missouri

Listed

October 14, 1966

Type

Site

Period

Listed

Ref No.

66000415

About this property

Research Cave, also known as the Arnold Research Cave and the Saltpetre Cave, and designated by the Smithsonian trinomial 23CY64, is a major Native American archaeological site near Portland, Missouri. Investigation of the site has uncovered evidence of human habitation as far back as 8,000 years. The site was designated a National Historic Landmark in 1964; it has been recommended for de-designation due to looting. The cave is located in an outcrop of sandstone approximately 2 miles (3.2 km) north of Portland, overlooking the Missouri River. The cave is substantially more than a rock shelter, with interior chambers accessible by low passages. When white settlers moved to the area in the early 19th century, one of them, John Phillips, began mining saltpetre from the cave for the manufacture of gunpowder. A later long-term owner was H.A. Arnold, giving the cave the name by which it is most commonly known. It has been the subject of archaeological interest since the mid-1950s, with intermixed materials that date back an estimate seven to ten thousand years. Finds at the cave are particularly notable for fine examples of footwear. The cave has produced several of North America's oldest human clothing finds including a pair of leather wrapped moccasins dating back 5,500 years ago. The site has been repeatedly disturbed, both by burrowing animals, and previously laid layers of cultural materials have been disturbed by subsequent occupants of the cave. By the early 1980s alterations to deposits at the cave mouth by the property owner had compromised some of the materials. National Register of Historic Places listings in Callaway County, Missouri

Location

Portland, Callaway County, Missouri

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Overview

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The Land

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Geology

The bedrock beneath the site, its age and rock type, reaching back millions of years.

LiDAR Terrain

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Conflict & War

The battles, raids and skirmishes fought near here, across every era of American conflict.

The Civil War

The Civil War on this ground, 1861 to 1865: who held it, and the battles, camps and regiments nearby.

The Soldiers

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Native Heritage

The Native nations who held this land, mapped across time from before European contact to today.

Settlement

Who claimed and held this ground, from Indigenous homelands through the colonial powers to the United States.

The Community

How the town grew, who came, and what kind of place it became, traced through the census record.

Rivers & Rail

The rivers, canals and railroads that connected this place between 1830 and 1911.

Notable People

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Finds & Access

Museum objects tied to the area, and the laws on searching, collecting and access here.

Literature

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Spotlight

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Questions about this property

When was Research Cave listed on the National Register?

Research Cave was listed on the National Register of Historic Places on October 14, 1966.

What type of historic resource is Research Cave?

Research Cave is classified as a site in the National Register of Historic Places.

Is Research Cave a National Historic Landmark?

Yes. Research Cave has been designated a National Historic Landmark (NHL), the highest level of federal recognition for historic properties in the United States.

What is the period of significance for Research Cave?

The period of significance for Research Cave is recorded as the listed era.

Can I research the history near Research Cave?

Yes. Aubrey Research reports search National Register listings, battlefield records, land patents, and other primary historical sources within any radius of a US address. A report for an address near Research Cave will include this listing and all other historical records in the area.

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