Yakushima is a small sub-tropical island off the end of Japan, it is a World Heritage Site because of the ancient forest. It is said to have inspired the forest in Princess Mononoke (you can see a section of the film here on YouTube).
We got there by hydrofoil passing the most southern point of mainland Japan on our way. On the island we hired a car which was a good idea as there is not a great deal of public transportation. There is one main road going round the edge of the island, this road on the west of the island is so narrow and bendy that buses can’t get through.
It is officially the wettest place in Japan and it was rainy while we were there, this was mainly while we were up high in the forest. Really this was part of the experience of Yakushima, the mist and the green dripping forest. Down by the shore where we were staying it was actually quite hot, and it was nice to get a breeze blowing in at night while the crickets were making a racket out in the darkness.
We saw lots of interesting wildlife including a snake, and the deer and monkeys of the forest were remarkably unafraid of us. The whole trip I used my 50mm Prime lens – so no zoom – so from the pictures I think you can see how close we could get. The monkeys were not a hassle grabbing things like they can be in other countries, they had funny red faces and bums.
Generally I would recommend you go to look at the waterfalls, the forest and the sea and relax. Go for a drive on the narrow road to the west of the island if you can as the views are beautiful and you will see a great many monkeys and deer. Stop off at the long white beaches where the turtles lay their eggs. This website has a lot of information on Yakushima and was very useful. The main souvenirs of the island seem to be things carved out of cedar wood, if you would like to bring gifts back we found that the shop in the Ferry Terminal actually had the greatest variety and the best prices.
Apart for the general advice to go to look at everything these are a few particular places we liked:
Various different treks of different difficulty and length.
A guided tour (in Japanese) around the fruits that can grow in this sub-tropical environment, so many varieties.