1. Mid-late 18th century grotto and associated standing stone, part of Piercefield Wye Walk (Nprn266015), set within the confines of a relict defended enclosure (Nprn307997).
To the west of the grotto, next to the path, is a small standing stone, to the east of which is a large deep rectangular rock-cut hole (? natural).
Taken from Long Text attached to Nprn266015.
J.Wiles 28.02.03

2. Depicted on the Second Edition Ordnance Survey 25-inch map of Monmouthshire XXVI, sheet 9 (1902). C.H. Nicholas, RCAHMW, 21st August 2006.