We live in Indianapolis so it was a short two hour trip to Marengo. We did the Drip Stone tour, which was about an hour in length. It was perfect for us, as our kids are 8 and 5. There is no crawling through mud, water, etc. We could comfortably walk through the cave without too much bending. I'm 5'5" but the taller people definitely had to duck for longer periods of time. The cave itself is a natural wonder. We've never been to one so I wasn't sure what to expect, but I would say it's a great intro tour for anyone interested.
The guide was very young, but did a good job of explaining things while on the tour. There are a couple of points in the tour that get pretty dark, so little ones might get a bit scared,but the majority of the tour was very well lit.
Not too much climbing, a couple of points in the middle of the tour and then at the end to get out, but it was not a strenuous tour at all.
The store where you buy tickets is clean and well kept as are the bathrooms.
I'd definitely recommend for those who've never tried it! It was $48 for two adults and two kids under 12.
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