This bank may have been much higher and there are suggestions the site could have been a sacred enclosure or Plen an Gwarry, which was a type of amphitheatre with rows of stone seats where feast days or fire festivals celebrating the Celtic solar god, Belenos, were held or where mystery plays were staged.
Other theories suggest a large disc barrow or an unfinished hill fort; the outer wall is not high enough to have been of any defensive value.
In the centre of the enclosure are three smaller circles arranged in a triangle, originally made of contiguous stones which have since been removed.
On Midsummer's Day, in recent times, the inhabitants, of this parish were greeted with sounds resembling the discharge of musketry in different directions, proceeding from holes bored in rocks, which being charged with powder were exploded in succession; and on the same day a new flag was displayed on every mine, and the night was ushered in with noisy festivities, and bonfires blazing on many of the hills.
[5][6] The name may also be derived from Tinne, the Druid name for the holly tree, the burning of which was associated with the death of the old year and the coming of the new one on Samhain or 31 October.