Entrance to Mt Widderin Caves. The entrance is quite steep and small. Handrails have been added to aid people's descent.

Cave Formation (Ollier, Brown)

Lava flows downhill due to gravity, and a crust forms. Layering occur, separated by vesicles and more liquid lava. Thickness of layers will increase with increasing velocity of lava, the flow is determined by ground slope also. The greater the rate of movement the thinner the flows, thus the lava becomes layered. The more congealed lava goes into the layers and the more liquid is concentrated between the laminae, which forms tubes. This mobile liquid eventually becomes concentrated in a few channels where the heat is the greatest. With solidification and remelting, flow and hydrostatic pressure are all working together, the end result is cylinders of liquid lava escaping due to a  breach in the toe of the flow or other various reasons. Thus a cave is left such as Mount Widderin
The final forms of lava depends on the viscosity of the liquid lava before withdrawal, rate of solidification and pressure changes in the liquid both before and after withdrawal.

Click on the picture to see a bigger version of the cave plan

The Lake chamber is entered through a narrow tunnel

 The ballroom was used for real balls at the turn of the 19 th century.

Bat guano, rich in phosphates has been mined from Mount Widderin caves. This guano has been the source of the rarest minerals that have made the caves famous in geological circles.