You can really feel the immense size of the Devils Coach House as
seen here from the start of the Self guiding cave (which is behind me).
The self Guiding cave is included in any of the paid cave tours and you
enter via a security token. What you see in the picture is however a free
exploration experience - of course you have to like steps!
Have a look at my GoPro Video http://youtu.be/NlzOZQRPZoY