“A near-complete Anglo-Saxon dwelling and oratory has been discovered, believed to date from the early ninth century” and located a few miles from Burton-upon-Trent. “The caves had long been considered to be 18th-century follies”, but a detailed new study by the Royal Agricultural University and Wessex Archaeology shows them to be much earlier.

The PDF is not yet online but the abstract has…

“… Saint Hardulph, a deposed Northumbrian king who seemingly retired as a hermit at this site. The fabric of the cave itself has [long been assumed to be 18th and 19th century, re:] nearby Foremarke Hall. Analysis shows that such a late origin for the structures is very unlikely, and that modifications in the 18th or 19th century were on a small-scale and saw no significant enlargement…”