Well it isn't really trekking, for those who need a day out of the water and on their feet, there are some solid walks to do on Ko Phi Phi.
The most popular walk is up to the viewpoint. There's actually three viewpoints (imaginatively named viewpoint 1, viewpoint 2 and viewpoint 3), with each offering an increasingly spectacular view of the sand isthmus of Ko Phi Phi.
The walk is moderately strenuous and you should be sure to wear a hat, apply sunscreen and take water. Water can also be purchased at the summit.
Once at the summit there are four trails that lead down to the remote east coast beaches. Ao Tohko, Paknam (Relax Beach), Rantee and Lo Bakao can all be reached on foot from the summit. It takes about 30 minutes to reach the first three and about an hour to reach Lo Bakao (from where you can walk onwards along the road to Laem Thong).
Another walk is to follow the trail from Ton Sai village along the beach to Long Beach. Once at Long Beach, walk up and through Phi Phi The Beach and keep following the road. After a while the road takes a sharp left, but you continue straight ahead down a dirt track that eventually runs through a coconut plantation to the lovely Lo Moo Dee beach.
A note on this beach: while there is nowhere to stay here, there is a small beach restaurant run by a couple of decidedly cantankerous Thais who have made it absolutely clear, in no uncertain terms, that Israelis are not welcome neither in the restaurant or on the beach. Given the prices they charge for anything, we're surprised anyone would want to give them business anyway. They've also now posted "Private Beach" signs up in the coconut grove approaching the beach – just ignore them. All beaches are (supposed to be) public in Thailand.
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