below, these observations are disputed by other investigators. For example, some investigators claim that where sand had washed away between the seams, another course of blocks can be seen along with small blocks underlying these blocks. However, detailed evidence that clearly documents the alleged presence of a continuous second layer (course) of stones beneath the stones forming the currently exposed "pavement" has not been published in a reputable, scientific venue with the detail that is needed for critical evaluation. Pictures posted on various Web pages of stones alleged to be artificial "wedge stones" and "prop stones" fail as convincing evidence for a second course of stones because they are typically smaller in size, do not form a continuous course, and too infrequently lie directly beneath the blocks that form the surface of the Bimini Road. This is not what would be expected of an actual underlying course of man-made masonry. David Zink states: This led him to conclude: In addition, early studies of the Bimini Road, i.e. Gifford and Ball and David Zink, report taking numerous samples and cores for examination. It is also safe to presume that a certain number of the innumerable visitors to the Bimini Road have chipped off pieces of it. Scientific sampling and souvenir hunting would have left behind modern "tool marks" on the various blocks composing the Bimini Road for later investigators to find. Age Attempts have been made to determine the age of this feature using different techniques. These include direct radiocarbon dating of the stones composing the Bimini Road and uranium-thorium dating of the marine limestone on which the Bimini Road lies. In 1978, the radiocarbon laboratory operated by the Department of Geology at the University of Miami dated samples from a core collected by E. A. Shinn in 1977 from the Bimini Road. In 1979, Calvert and others reported dates of 2780±70 yr BP (UM-1359), 3500±80 yr BP (UM-1360), and 3350±90 yr BP (UM-1361) from whole-rock samples; a date of 3510±70 yr BP (UM-1362), from shells extracted from the beachrock core; and dates of 2770±80 yr BP (UM-1364) and 2840±70 yr BP (UM-1365) from carbonate cementing the beachrock core. These dates are temporally consistent in that the shells composing the beachrock core from the Bimini Road dated older than the cement holding them together as beachrock. These dates can be interpreted as indicating that the shells composing the Bimini Road are,