(click image to enlarge)
In executing the cuttings on this part of the line, both above and below this bridge, as well as in a cutting about a mile father along, a number of rounded pebbles and masses of whinstone of considerable size were found; strongly indicating that at some remote period this part of the valley has been a lake, whose waters have been gradually displaced by the accumulated deposits of the stream brought down from the hills and dales above.
(Henry Belcher, Scenery of the Whitby and Pickering Railway, page 27-28)