The Iriomote island crossing (西表島のジャングルを横断) is a difficult but very beautiful river and rainforest hike across Iriomote. The hike is not well-marked, has no cell service, and lots of leeches. Also, large parts of the hike are in the riverbed, and it's easy to slip. I would not do this hike during bad weather because of flash floods, and I would not recommend doing it alone either. It also requires a lot of planning because of the boat access, the long duration/not enough daylight, and the public transportation. Additionlly you need to register the hike with the local police and forestry office.
The island recommends a guide, and depending on who you talk to, they will actively try to convince you not to go. If you're an experienced hiker, especially with spotting trail markers (it's easy to get lost), then there is no need in my opinion.
Lastly, have a look at the distance and sunlight hours. We got out of the jungle just before sunset. Iriomote has venomous snakes (habu) which usually come out after sunset, that means you should be sure you're out of the jungle by then.
Honestly planing this hike was such a pain and definitely the most complicated hike I've done in Japan. I hope with this post it will be a bit easier for you because despite the challenges, hiking across the island was an awesome experience and I loved it. So, prepare carefully and enjoy the beautiful scenery along the way!
Time: 10h (incl. 1:40min break)
Location: Iriomote, Okinawa
Elevation Gain: 807m
Start at the boat tour dock (下流船着場) for the urauchi river. Take the first boat, which should be at 9:00 am, but check their website beforehand for departure times. They have toilets, snacks, and showers there. Make sure to come early, because they made us fill out some from again (that we had already filled out at the police/forestry department). Then get a one-way ticket for the boat. I don't remember the exact price but it was around 2000¥
Since public transportation is limited on the island I would recomend to either rent a car and park it at the end of the trailhead (close to Otomi village) or stay somewhere close to it and have your guesthouse drive you to the boat dock. If you take the first bus up to the boat, you will not have enough time for the hike!
We parked our rental car at the end the day before, then took a bus back up north (60min) and stayed close to the boat dock and walked to it in the morning.
The road up to the trailhead was locked and we parked next to the road close to the cemetary. If you get a guide they can drive up as far as I know/have a key.
Taxis are another option, but since the drive is an hour we didn't want to spend that kind of money.
When you get off the boat the first part of the hike is well maintained and a nice little rock path. Until Maryude and Kanpire waterfall you should have no problems at all. It took us about 30min to get there.
After that is where the real fun begins. You'll walk up in the riverbed, either directly in the water or in mud. Sometimes the trail is easy to spot and other times you will have no idea if you're still on trail. Keep a constant lookout for the little pink ribbons and if you don't see any for a while go back.
Sometimes the trail will follow a small riverbed in the jungle, other times it will go into the rainforest. These parts were especially tricky to spot and my friend walked off trail a couple of times.
There are a couple of narrow sections and one or two ropes but nothing technical. The main challenge of this hike is not to get lost or take too long.
The last hour or so will be on a gravel road back to the car and downhill.
Ski socks over pants worked well and none got through. My friend was wearing thinner socks and they were able to bite through. As you can see one of us wasn't wearing any socks and he peed on his legs/feet throughout the day, he didn't have any either. Pick whichever you're most compfortable with ;) but there are a lot of leeches. I picked maybe 30-40 off of my socks.
Also if they do get through, salt works. They come right off.
Elevation Profile & Map
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