The main tourist attractions are big-game hunting in the forests of the south, boat excursions down the Nile through the forest and desert, deep-sea fishing, the Red Sea Hills, the underwater gardens at Port Sudan, and archaeological sites in the north. Horse racing has been popular in the Sudan since its introduction in 1929. However, since the civil war and the advent of Islamic rule, tourism in the Sudan is virtually nonexistent. There were 38,000 tourist arrivals in 2000, generating receipts of $5 million. In 1999, there were 4,545 hotel rooms with 7,907 beds. Visitors to the Sudan require a passport and a visa. Precautions against cholera, typhoid, tetanus, meningitis, yellow fever, and malaria are recommended. According to 1999 UN estimates, the cost of staying in Khartoum ranges from $101–208 per day depending on the choice of hotel.