Yes. It is over flat but uneven surfaces. Parts are wet and puddles are common. Wear solid footwear. Inside the mine it will be damp and cool.
Yes, it is very interesting
Yes, you walk with the tour guide
Yes, it is approximately a 2 hour tour with a guide. It is super educational and fun! I would highly recommend wearing a good set of shoes, since the flooring isn't always even. The cave also sits at 55 deg F, so if you are someone who gets cold easily, make sure to pack a sweater.
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