Tunnel is a free Java 2.5D cave drawing program surveys based on Survex-compatible data which can also read and PocketTopo files.

It is used primarily to draw up CUCC Austria caves and the Three Counties System.

The defining feature (ie why you cannot use a standard drawing software for this application) is the ability to distort the maps to fit to changes to the underlying survey network.

The main alternative to Tunnel is Therion, which also solves this problem, but in a completely different manner and with a slightly steeper learning curve.


Download tunnel2014-08-31.jar and runtunnel2014-08-31.bat (if you are in Windows) from the downloads page, and double-click on the latter file

Read the inline help file online or from within the program.