The bottom of the pit could be prepared with sand and gravel then filled with concrete. Square sandstone or any other stone bricks may construct the walls or an easy even basin can be built with concrete.
Down while using floor inside of first junction room may be the route to your Signature Room, a good trip for brand spanking new cavers, with plenty of good sticky mud. The well-worn path up the rock on the left is hard climb, but easy to come down on the way out. There can be a sloping rock in the centre of the passage that will have a distinct crack for virtually any foot step followed by another sloping rock with one small worn formation in the middle that provides another foot step to the very top of the climb. Some more steps and you will be looking down a steep climb down with an appreciable overhanging boulder on very best and the vertical wall on the left.
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