Crater of Diamonds State Park is a 911-acre (369 ha) Arkansas state park in Pike County, Arkansas, in the United States. The park features a 37.5-acre (15.2-hectare) plowed field, one of the few diamond-bearing sites accessible to the public. Diamonds have been discovered in the field continuously since 1906, including the graded-perfect Strawn-Wagner Diamond, found in 1990, and the Uncle Sam, found in 1924, which at over 40 carats is the largest diamond ever found in the United States.

Pike County is a county located in the U.S. state of Arkansas. As of the 2020 census, the population was 10,171. The county seat is Murfreesboro. Pike County is Arkansas's 25th county, formed on November 1, 1833, and named for Lieutenant Zebulon Pike, the explorer for whom Pikes Peak is named. It is an alcohol prohibition or dry county.