Covering about 263 square km (164 square miles) of Cat Ba Island is this national park where 32 species of mammals, including the endangered langur monkey, live among the jungle terrain and freshwater lakes. Within its tropical rain forest are 78 species of birds and 20 species of reptiles. In addition to impressive beaches and mangroves, within its boundaries are two historical caves once used as clinics during the Vietnam War. Active travelers can tackle the reserve
by hiking the demanding (yet rewarding) 18-km (11-mile) Cang Viet Hai Trail across the park. The best views are from the park's observation tower, but the climb up metal ladders and cliffs are not for the faint of heart.
Trung Trang, 30 minutes from Cat Ba Town, Halong Bay, Vietnam