Black Cave, or Spanish Treasure Cave, as it is often called, is just off State Highway 59, between the towns of Gravette and Sulphur Springs in northwest Benton County, Arkansas. It is thought to be the location of a mine excavated by the Spaniards during one of their early expeditions to this region. The cave was in the side of a cliff, and near it stood a large oak tree on which was carved a map.
In the early 1900s, a strange Spaniard appeared in the county, claiming to have information about a treasure buried in the cave. Naming $3,000,000 as the value of the treasure, he interested a group of men who formed an exploration company. After examining the cave for about one mile and finding nothing, the search for the mysterious Spaniard’s gold was abandoned.