Take insect repellent. Loads of it. Also wear old clothes as the dirt/clay stains your clothes. There are parts where you semi-abseil using rope. We went without a guide and managed fine, but there was one spot in particular where we went the wrong way for a while and had to double back. Awesome feeling of achievement and there is a waterhole at the end. You go from one side of the island to the other. We got a ride up to the start (the road is quite long). We went January 2012.
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