A landslide has revealed the remains of a medieval cave shrine near Guildford, Surrey. The shallow sandstone cave was discovered by rail workers repairing train lines after the landslide sheered off the embankment above last December.

NetworkRail called in archaeological contractors to investigate the find. The team had to abseil to reach the cave and inspect its decoration. The central decoration is a deeply carved niche in the shape of a pointed Gothic arch dotted with cup cut-outs. Next to it is a cross atop Calvary. They found carvings of another seven or eight Gothic niches on the wall (they’re heavily worn and can be hard to distinguish) and initials and other markings on the ceiling of the cave. The remains of what are believed to be two fire-pits were discovered on the floor and a black substance on the ceiling may be soot, either from the fires or from lamps.

A spokesperson from Archaeology South East, said: “The cave contained what appear to be shrines or decorative niches, together with carved initials and other markings. The old name for St Catherine’s Hill is Drakehull ‘The Hill of the Dragon’, so this has obviously been a site of ritual significance long before the construction of the church on the top of the hill in the late 13th century.

“Work is underway to analyse soot and charcoal found inside the cave, which will hopefully tell us more about how and when it was used.”

What is left of the cavern today is relatively small, with ceiling heights ranging from one to just over two feet, but it was much larger in its medieval heyday. Construction of the railway cut through the hill in the 1840s, leaving only this section of the cave intact.

Mark Killick, Network Rail Wessex route director, said: “This is an unexpected and fascinating discovery that helps to visualise and understand the rich history of the area.

“A full and detailed record of the cave has been made and every effort will be made to preserve elements where possible during the regrading of the delicate and vulnerable sandstone cutting.”