Photo: Binh Giang, Public domain via Wikimedia Commons
The domain of the endangered Cat Ba Langur, of which there are supposed to be only around 100 left. Things on offer include a walk to a peak viewing tower (1½-2 hr round trip; slippery and muddy if it's rained recently), a frog pond (probably better in the off (wet) season), a short nature walk near the frog pond, more stuff which you can probably find online.
Cát Bà National Park is a World Heritage Site designated as a biosphere reserve in northern Vietnam. The park is part of Cát Bà Island in Hạ Long Bay and is administered by the city of Haiphong. The park is located approximately 30 kilometres (19 mi) east of Hai Phong, covering about 263 square kilometres (102 sq mi) and comprising 173 square kilometres (67 sq mi) of land and 90 square kilometres (35 sq mi) of inshore water.
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