In addition to several little-visited sandy beaches along the Gulf of Tadjoura, tourist attractions include islands in the Gulf of Tadjoura and the Bab alMandab. At Goubbet alKharab, at the western end of the Gulf of Tadjoura, there are steep cliffs and a bay turned dark green by black lava. Inland from this point is Lake Assal with a number of active volcanoes nearby. The Forest of the Day is a national park for rare trees on Mt. Goda. In the south, the alkaline Lake Abbé is visited by flocks of flamingos, ibis, and pelicans. Near Ali Sabieh are the famous red mountains and a national park full of various gazelles. Passports and visas must be secured in advance; antimalarial precautions are advisable. In 1998 an estimated 21,000 tourists visited Djibouti. In 2001, the US government estimated the cost of staying in Djibouti at $229 per day, depending upon the choice of hotel. Stays in other areas, however, can be considerably less, even as low as about $80 per day.