1974, the Imperial War Museum was approached by the government and asked to consider taking over the administration of the site. A feasibility study was prepared but came to nothing, the museum feeling it did not have sufficient resources to commit to the War Rooms. In 1981, Prime Minister Margaret Thatcher, known as an admirer of Winston Churchill, expressed the hope that the Rooms could be opened before the next general election. The Imperial War Museum was again approached. Initially still reluctant, the museum's trustees decided in January 1982 that the museum would take over the site, on the understanding that the government would make the necessary resources available. The initial costs were to be met by the Department for the Environment and the War Rooms intended to be self-supporting thereafter. The Rooms were opened to the public by Mrs Thatcher on 4 April 1984 in a ceremony attended by Churchill family members and former Cabinet War Rooms staff. At first the Rooms were administered by the museum on behalf of Department for the Environment; in 1989 responsibility was transferred to the Imperial War Museum. Following a major expansion in 2003, a suite of rooms used as accommodation by Churchill, his wife and close associates, was added to the museum. The restoration of these rooms, which after the war had been stripped of furnishings and used for storage, cost £7.5 million. Churchill Museum In 2005 the War Rooms were rebranded as the Churchill Museum and Cabinet War Rooms, with of the site redeveloped as a biographical museum exploring Churchill's life, the development of which cost a further £6 million raised from private funds. The museum makes extensive use of audiovisual technology. The centrepiece is a 15-metre interactive table that enables visitors to access digitised material, particularly from the Churchill Archives Centre, via an 'electronic filing cabinet'. The Churchill Museum won the 2006 Council of Europe Museum Prize. During 2009–2011 the museum received over 300,000 visitors a year. In May 2010 the name of the museum was shortened to Churchill War Rooms. In June 2012 the museum's entrance was redesigned by Clash Architects with consulting engineers Price & Myers. Intended to act as a 'beacon' for the museum, the new external design included a faceted bronze entranceway, and the interior showed the cleaned and restored Portland stone walls of the Treasury building and Clive Steps. The design was described as 'appropriately