Copenhagen's opera house is the national house of ballet and opera in the country, and one of the most modern in the world. The construction cost over 300 million euros, it is one of the most expensive buildings ever built for an opera. The building was donated to the government by the company Mærsk, creating a controversy because such donations are tax free. Therefore is was somewhat like forcing the state to build an opera. The building is located in Copenhagen on the other side of the harbour which is compated to the palace of Amalienborg, in line with the marble church. You can reach it by boat to see the classic structure and return to the centre again by water.