The Core Research Center (CRC) was established in 1974 by the U.S. Geological Survey (USGS) to preserve valuable rock cores for use by scientists and educators from government, industry, and academia. The cylindrical sections of rock are permanently stored and available for examination and testing at the core storage and research facility in Denver, Colorado. The CRC is currently one of the largest and most heavily used public core repositories in the United States. The CRC encourages use of its facility by all interested parties. Tours of the facility are available by appointment.