The Ai river in southwest Sarawak (near Lubok Antu) was dammed in 1985, thereby creating a huge 90 kmĀ² lake, the Batang Ai reservoir. The lake is 250km from Kuching, a 4-5 hours drive by car. The only hotel in the area is the Batang Ai Hilton, which is located on a promontory of the lake and is only accessible by boat. Other Accommodation in the area is offered by longhouses, for which it is necessary to book a tour. The area is populated by Iban people, many of whom were relocated when the lake area was flooded following the completion of the dam in 1985. The vegetation around the lake consists mostly of secondary rainforest. To see more unspoilt nature it is necessary to go further upriver (for instance with a tour operator). The Batang Ai national park is located about 15km upriver from the dam. It covers an area of 24km and extends into Indonesia, consisting of the Lanjak-Entimau wildlife sanctuary in Malaysia and the Bentuang-Karimun national park in Indonesia.