You will be picked up at your hotel in Hanoi for driving to Cuc Phuong, about 140 km south of Hanoi by road, is one of Vietnam's oldest national parks and consequently one of the best managed. It's approximately 22, 000ha of subtropical forest and karst limestone scenery, and home to an extraordinary range of unique species. Apart from exploring the forest, you'll visit the park's Endangered Primate Centre, where you'll be able to see two of the rarest species in the world, the critically endangered Delacour and Cat Ba langurs. Stay overnight at National Park guest house. Note: The best time to visit Cuc Phuong is from October to May. Avoid the summer as the parks biodiversity includes a large contingent of leeches that get hungry in hot humid weather. April to May sees clouds of millions of butterflies spiralling in pockets of sunshine.