While digging a cellar under his property in 1936, Thomas W Kenny (1899-1975), a resident of Plateau City (near Grand Junction, Colorado, USA), is said to have discovered a tiled floor. It was found at a depth of 3 metres (ten feet) and consisted of tiles set in mortar. Allegedly, they were dated at between 20,000 and 80,000 years old, although the technique used to date them is not stated, and lay in a Miocene geological stratum.

The story first appeared in Frank Edwards’ Strangest of All (1956) and the above account is all the detail we have. Nothing about the composition of the ‘tiles’, nothing about their size, nothing about the layout, nothing about the technique that allowed them to be dated, nothing about the identity of their discoverer. In short, nothing that would enable an assessment of the story to be made. We have to take everything on trust. And a sceptical approach requires us to ask awkward questions. Were the ‘tiles’ of even size and thickness? What was the nature of the ‘mortar’ in which they were set? Is there anything in the local geology that might resemble tiles and mortar? Without answers to these questions, the little information we have been given is worse than useless.