Near the highest point of Trefil Ddu, part of Llangynidr Moor, this is the entrance to a network of subterranean caves originally called Tylles Fawr, and better known as the Chartist Cave after it was used by Chartist rebels as a weapons store prior to their attack on Newport later the same year. Extensive caves lead off the first chamber. (Please note that exploring underground caves is potentially very dangerous.)
Newport and Valleys pictures