subsidy from the state of Brandenburg. The building permit for constructing the theme park inside the hall was granted on 2 February 2004 and Tropical Islands officially opened on 19 December 2004. Inside the hall, the air temperature is and air humidity is around 64%. Tropical Islands is home to the biggest indoor rainforest in the world, a beach, many tropical plants and a number of swimming pools, bars and restaurants. It is open around the clock, every day of the year – except on Christmas Eve. On entering the hall, visitors choose between different basic admission options with different prices. Tropical Islands is divided into two main areas, each with its own admission price. Visitors can move from one area to the other by paying an additional daily charge. Additional charges also apply for areas such as the water slide tower (not always), crazy golf course, African Jungle Lift, evening show and internal accommodation area. The entertainment programme comprises a gala evening show, smaller shows during the day and various events. Themed areas Tropical Islands has a number of different themed areas: The Tropical Village, featuring copies of traditional buildings from Thailand, Borneo, Samoa and Bali. The Rainforest, with around 50,000 plants and 600 different species, including some rare plants. The Tropical Sea, a pool with an area of and a depth of , designed to look like the waters of a coral island and a sandy beach. The Bali Lagoon, with an area of and a depth of less than in places, with fountains, a current canal, whirlpools and two water slides. The Amazonia, an outdoor area of over with two large pools, a sunbathing area, a beach volleyball and beach soccer field, as well as a kiosk. Further development A children's play area opened in 2007. In mid-2007, a sauna and spa facility with six separate areas was added, the largest tropical sauna complex in Europe. The design of the saunas is inspired by UNESCO World Heritage Sites in South-East Asia, including a cave temple on Elephanta Island in India and the Angkor Wat temple in Cambodia. The bathing area includes a high water slide tower with four slides, a children's play area and a crazy golf course. According to figures published by the company, Tropical Islands has spent EUR 23 million on further development and expansion work. The original total investment sum announced was EUR 75