It was said in the 19th century a family squatted in the surviving chambered tomb on the right! The monuments form part of an unusual tradition on Anglesey of 'long graves' comprising of several megalithic chambered tombs in sequence. This is but one site, and includes others such as Din Dryfol, Trefignath, Hendrefor and Plas Newydd.

Edit: well that's annoying, the image didn't attach to the OP! I've added it as a comment below, apologies!

Edit x2: It works now, odd!

The Rudston Monolith is the largest single standing stone in the U.K., standing at almost 8m tall above ground. Experiencing it was a lovely end to my little adventure exploring the NE of England 🥰