Land use is commonly understood to be a surface designation—with categories and ownership relatively unambiguous across a site’s breadth. But in one of the most thrilling stratifications of land use in the region, the Rock City complex layers multiple land uses with the same site—recreation, relocation, and record administration. Here, surface and subsurface are separated into at least two primary uses—capitalizing on a legal instrument known as mineral rights. Long the site of a limestone quarry, the site has been exhausted of its stone since mid-century, with the vast rooms of the quarry sitting empty or occupied by provisional uses such as mushroom production. In its most recent inhabitation, the subterranean quarry is now a vast cold-storage facility, with the Salt Lick Point trail occupying the surface.

As part of the land acquisition for the town of New Valmeyer following relocation after the flood of 1993, the city was required to also purchase the 6,000,000 square-foot subterranean limestone quarry. Mined using the ”room and pillar” method, the quarries were seen by many in the community as an obstacle to development; but at least one regional resident saw in the vast underground spaces an opportunity. Owner Joe Kopeis has developed over half of the caverns as the Gateway Cold Storage facility—which counts as its tenants Little Caesars Pizza, Breyers Ice Cream, and the National Archives and Record Administration (NARA).

The NARA facility, with its prefabricated concrete entryways and eagle seal incongruously merged with the limestone bluff face, is dedicated to the storage of 2 million cubic feet of civilian personnel records. Nestled in the voids of the quarry is a 400,000 square-foot building that houses most personnel records produced since 1973. The facility opened in 2009 after a fire at NARA’s St. Louis County facility, and currently works in conjunction with the NARA Dunn Road building, where another 2.3 million cubic feet of records are stored.

Prior to its transformation into the technologically robust document and cold-storage facility we know today, the quarried cavern space was most notably used for the production of mushrooms. Beginning in 1948, the Knaust Mushroom Company leased a 110 acre section of the caverns and began raising and harvesting mushrooms in 1951. As noted above, temperature and humidity were relatively easy to control, and in the stable, moist cavern conditions the firm was able to achieve optimum growth. At one time, Knaust was the largest mushroom grower in the world, but the operation was sold to a different producer in 1974, and the overall operation was phased out by 1981. During one growing season, almost 2 million pounds of mushrooms were grown in this subterranean facility. A cave full of fungi deep in the limestone geology of the American Bottom bluff-line.

Sitting atop the cave-like quarry is the Salt Lick Point trail, so-named after a major manufactory of salt that was operated here as early as 1802. The trail is part of a distributed system of public access points that the Illinois Department of Natural Resources have made available along the woody talus edges of the bluff. Here, one can experience the upland forests that still define this seam and that give the American Bottom its rich fall colors.