Moorland cave
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.)