Ki Eun Pyo
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One of the top things to do on this island.
You have to buy a guided tour to enter, but it's worth it. Our guide Chris explained about the history of the caves, showed a few iguanas that we met on the way to the caves, and gave a detailed background on how the caves became available for public view.
We were shown three caves, and the last one had the biggest size and depth.
Due to mosquitos, they provide insect repellants at the site, but I highly recommend that you bring the one that works best for you.
I recommend bringing a flashlight since it helps with walking certain sections that are not lighted well. Also, a good sturdy pair of shoes is definitely helpful, since there are stairs and some grounds are slanted.
There are bats inside the biggest cave, which was very interesting to watch.