Naantali are some important points of interest in the city, such as the Moomin World theme park on the island of Kailo. Naantali Spa Hotel, the largest spa in the Nordic countries, and the Naantali’s medieval convent stone church. The city's popularity as a tourist venue is highlighted by the fact that the official summer residence of the President of Finland, the Kultaranta estate, is located on Luonnonmaa. The archipelago sea boat traffic is handled by S/S Ukkopekka. Old steamship cruise Naantali-Turku-Naantali. Naantali hosts an international music festival every June, and the traditional Sleepyhead Day carnival in July. In addition to
Sophia Jansson "Jaana" in 1965. In May 2003, The Finnish Embassy in London arranged for events to surround the recent translation of Tove Jansson's 1972 "Sommarboken", a novel which featured the fictionalized life of the young Sophia on an island. During this event, publishers presented works by Sophia Jansson and Johanna Sinisalo. Jansson was later interviewed in June 2003 by "The Daily Telegraph" where she explained the details surrounding the story presented in "Sommarboken" and the relationship shared between Jansson and her aunt, Tove Jansson. She would write in more detail about this topic in 2006 in the Scandinavian Review, and again