Two entrances to Jet workings are located around Bold Venture Gill. The workings extend perhaps 20m in a grid pattern.
The tunnels are large enough to stand upright in and have very few collapsed areas.
This second set of jet working located nearby are much more unstable, three holes surrounded by fencing have opened up. The floor inside is littered with collapses and it can only be a matter of time before they totally collapse.
This whole area of the woodland shows much evidence of collpases from jet workings just below the surface and many more must still exist.