English: Twm Sion Cati's cave This is the legendary hideout of Twm Sion Cati, the Welsh equivalent of Robin Hood, whose exploits are based in the mid 16th century. While his youthful doings have probably been embellished over the years by story tellers, the real man, Thomas Jones, did exist and was born in 1530 and died around 1620. In his latter years it's known that he was given a royal pardon for his misdemeanours and his reputation of being a thief was probably forgotten as, among other things, he became a justice of the peace and was known as a Welsh historian.

The cave itself is on Dinas Hill, today managed by the RSPB and is quite an experience to visit. Although quite small and a bit of a contortion is needed to enter, large amounts of graffiti have been scratched onto its walls over the years, some of it with dates indicating that they were written nearly 200 years ago. What's obvious is that the calligraphy used in older graffiti was far superior to the more recent scratchings!

It doesn't appear to have been created by erosion, but by some major geological event in the past that fractured the surrounding cliffside.