In case you wondered

The picture you just clicked-on was created by using real cave survey information from Ogof Ffynnon Ddu II as input for a ray-tracing program called Polyray. The colours represent different heights above sea level.

Polyray is a shareware program and is written to run on PCs (386+387 upwards). It can be acquired from the internet or directly from the author.

Alexander R. Enzmann