Rockwall is a city in Rockwall County, Texas, United States, which is part of the Dallas/Fort Worth Metroplex. It is the county seat of Rockwall County. The population was 37,490 at the 2010 census. The name Rockwall is derived from a naturally jointed geological formation, which has the appearance of an artificial wall.The association of Paleo-Indian artifacts with extinct Pleistocene mammal remains in various archeological sites within in the Texas Prairie-Savannah Region of eastern North Central Texas, including a site in Collin County and Clovis points recovered from the Brushy Creek Clovis Site in Hunt County, demonstrates that Rockwall region was occupied by prehistoric Native American cultures at least as far back as 13,500 to 13,000 years ago.
More recently, the Rockwall region was occupied by Caddo Indians. Creek Indians moved to the area in the early 19th century. In 1851, as the first Anglo-American settlers moved to the area, they started to dig wells. During the digging, they found large underground rock walls that were initially believed to be manmade. Later study of the wall-like features by geologists and archaeologists found them to be jointed, natural sandstone dikes that had intruded Cretaceous marl. In 2013, forensic geologist, Scott Wolter, on the television show America Unearthed, visited Rockwall to investigate the claims that the wall might have been manmade, and the conclusion of the episode was that the underground structure was natural and not man-made.
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