We were there Last November 2012. The park is beautiful for trekking. Many people will spend more than 8 hours just to walk up there. We did for 4.30 hours. On the trail, you will find foods and drinks vendors and beautiful views on each stops section trail. When you were up on the top, you still have to walk to the campground for another 45-60 minutes. You can rent the bicycle at the arrival point and ride to the campground and return there (the cost of rental is a little expensive).
You also can rent the bicycle daily to go around the park (again is a little expensive). There are plenty of foods vendors up in the campground so you don't need to bring much food there. All views point spots in the park are far apart from the campground, so you need to walk from 45 minutes to couple hours to see the views (some 5-10 km one way). So bicycle is useful for a long distance of walks but the price is very steeps. If it is raining or after rain, beware of Leeches on the wet grasses in the campground bring foot protections along or purchase in the campground. We spend only one night there but definetely return when we have more time and better prepared.
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