It is uncertain exactly how the cave got its name. A skeleton of a "giant human" was supposedly discovered in the cave around 1700, but was lost when a local surgeon named Mr. Pye took the skeleton to sea on a voyage to Jamaica and his ship sank. The cave is shrouded in local superstition and is believed to have had a part in the early legend of King Vortigern, a native British king who fought against the invading Anglo Saxons. Vortigern is said to have made his last stand against Aurelius at nearby Ganarew. Lawman mentions a castle on Cloard Hill in the district of Hergin, and has Vortigern dying after the castle was besieged and fired by Aurelius and Uther. Helen Hill Miller, in her 1969 bookThe Realms of Arthur, suggests a military use for the cave, arguing that the cave's "recesses penetrate very far into the hill, and could hide a substantial force". The cave has a parallel with Cadbury Castle in that it is a cave within a hillfort.
Excavations
In 1871 the caves were excavated by Reverend William S. Symonds, after he learned that some miners had raided them. He unearthed hyena, lion, brown bear, red deer, rhinoceros, Irish Elk, reindeer, and horse bones dated to the Late Pleistocene. The evidence of hyena was particularly prominent and many of the bones showed signs of being crunched by them. He also found flint implements from the Upper Palaeolithic and fragments of Neolithic pottery. Members of the Cotswold Naturalists' Field Club also explored the caves, under the supervision of the Reverend Symonds, which led to further remarkable discoveries. They initially inspected one of the Doward caves, situated about 200 yards from King Arthur's Cave: Between 1925 and 1927 the University of Bristol Spelæological Society excavated here, and in 1926 Garrod dated his findings in the upper cave to the Upper Palaeolithic and those from the lower cave to the Middle Palaeolithic. The society returned in 1955 but found nothing new. In 1989, the caves and the Upper Wye Gorge of some 1.5 hectares was designated a SSSI.
Structure
The cave is said to "consist of a broad entrance platform, a double interconnected entrance and two main chambers", about 300 feet above the River Wye. One of the chambers is large and circular in shape, about 25 feet in diameter. The main chambers obtained the names Bear's Den and Lion's Cave due to the paleontological items found there. There are also several other open rooms to the cave.