There is a road that leads through the gorge, but it is only open to light vehicles.
It used to be believed that the pass was a collapsed cave, but modern geologists have discovered a more complex and ancient origin.
About 339 - 336 million years ago there were two areas of coral reef underwater with a shallow channel between them.
By 290 million years ago the reef was buried under 3km of rock.
Earth movements lifted the rocks out of the sea and over millions of years the wind and water slowly wore away the layers of sandstone and exposed the buried reef.
The ground was still frozen so the water could not penetrate it.
The huge torrent of water wore away the last of the shales revealing the limestone and the dramatic pass of Winnats.
A number of the larger cave structures have become commercial concerns, but there are still many unexplored caves in and around the area of Winnats Pass.
Although it is possible to drive up the pass, by far the best way to appreciate the size and splendour of the gorge is to walk up and down. This takes about half an hour, but longer if you want to explore the entrances to the caves along the way.
