The Lawrence Welk caves are talus caves formed between large boulders. Over time, washed out the soil between the boulders leaving space in between, forming tight "caves". These caves were relatively unheard of until the 70's when a few kids went missing, prompting a search and introducing the caves to the public.
This is a very tight and claustrophobic adventure. It is not for the faint of heart. This is an intricate maze with multiple levels. There is nothing safe about it and is possible to get lost or very injured inside. The caves go about 30 feet underground.
Make sure you mark your way in so you can find your way out again. I would believe that this trip is not for your average person. You definitely want to go with a few other people, bring headlamps and let others know where you're going in case something goes wrong.
Update: I have had the owner of this land write me and ask to remove directions. He has since built a family home on the property and says it is absolutely off limits. Please do not visit here.