Hang Nga guesthouse, popularly known as the Crazy House is an unconventional building designed and constructed by Vietnamese architect Dang Viet Nga in Dà Lat, Vietnam. Described as a fairy tale house, the building's overall design resembles a giant tree, incorporating sculptured design elements representing natural forms such as animals, mushrooms, spider webs and caves. Its architecture, comprising complex, organic, non-rectilinear shapes, has been described as expressionist. Nga has acknowledged the inspiration of Catalan architect Antoni Gaudí in the building's design, and visitors have variously drawn parallels between it and the works of artists such as Salvador Dalí and Walt Disney. Since its opening in 1990, the building has gained recognition for its unique architecture, being highlighted in numerous guidebooks and listed as one of the worlds ten most bizarre buildings in the Chinese People's Daily. The work is in progress since 1990.