Do you make bookings prior or is it payable on arrival?
I have never made a booking before. Just arrived and paid, and waited for the next available tour. I think if you want to do the deeper tour that goes way further into the caves, you have to book in advance. It's their extreme cave crawling tour where you crawl through tiny tunnels and swim through water, etc... But the standard tour doesn't require you to book in advance.
I assume one can book in advance but most people just rock up to the reception desk in the mouth of the cave (excuse the pun).
ON busier days one can expect to wait a bit for your tour after you paid, as people are taken through the cave in groups by a guide.
Pay on arrival.
The guided tour into the cave is payable on arrival, however you need to check the timetable for the tours
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