The Bimini Road, sometimes called the Bimini Wall, is an underwater rock formation near North Bimini island in the Bahamas. The Road consists of a -long northeast-southwest linear feature composed of roughly rectangular limestone blocks. Various claims have been made for this feature being either a wall, road, pier, breakwater, or other man-made structure. However, credible evidence or arguments are lacking for such an origin. Physical characteristics On September 2, 1968, while diving in three fathoms () of water off the northwest coast of North Bimini island, Joseph Manson Valentine, Jacques Mayol and Robert Angove encountered what they called a "pavement" of what later was found to be noticeably rounded stones of varying size and thickness. These stones form a northeast-southwest linear feature, which is now commonly known as either the "Bimini Road" or "Bimini Wall". Two similar linear features lie parallel to and shoreward of the Bimini Wall. The Bimini Wall and two linear features lying shoreward of it are composed of flat-lying, tabular, and roughly rectangular, polygonal, and irregular blocks. Descriptions of the Bimini Road found in various books and articles greatly exaggerate the regularity and rectangularity of the blocks composing these features. The Bimini Road, the largest of three linear features, is long, a northeast/southwest-trending feature with a pronounced hook at its southwest end. It consists of stone blocks measuring as much as 3-4 metres (9-12 feet) in horizontal dimensions, with the average size being 2-3 metres (6-9 feet). The larger blocks show complementary edges, which are lacking in the smaller blocks. The two narrower and shorter, approximately -long linear features lying shoreward of the Bimini Road consist of smaller tabular stone blocks that are only in maximum horizontal breadth. Having rounded corners, the blocks composing these pavements resemble giant loaves of bread. The blocks consist of limestone composed of carbonate-cemented shell hash that is called "beachrock". Beachrock is native to the Bahamas. The highly rounded nature of the blocks forming the Bimini Road indicates that a significant thickness of their original surface has been removed by biological, physical, and chemical processes. Given the degree to which these blocks have been eroded, it is highly implausible that any original surface features, including any tool marks and inscriptions, would have survived this degree of erosion. After a very detailed examination of the Bimini Road and the other linear features, Gifford and Ball made the following observations: As noted