The best time to visit Cuc Phuong National Park is during the dry season, from December to April, when the hard forest rain accounting for 90% of the annual rainfall is over. There are plenty of plants and mammals living in the park. There are an estimated 2,000 different species of flora and the 450 species fauna account for 38% of the national fauna. The vegetation cover is classified into three types. The flora is quite a treasure with a wide variety of 1,944 species, 908 genuses and 229 families. Especially it is enjoyable to touch the thousand-year-old cho xanh (parashrea stellata) and sau (Dracontomelum Duperranum or Dancorra Edulis) trees, 50-70m high. This natural reserve is covered with 2,000 species of plants. Especially orchid flowers are abundant with 50 species, some of which blossom and have aroma all year around. The fauna is diversified represented by 71 animal species, 319 bird species, 33 reptile species, and 16 amphibian species. Rare species include the bear, horse, wild boar, tiger, leopard, fox, squirrel, monkey, etc. A large area, for half-natural breeding, is reserved for raising wild animals such as the spotted deer, deer, golden monkey, langur (vooc quan dui), flying squirrel, draco (than lan bay) and for research. The Park is also home to hundreds of beautiful and strange birds and butterflies.