The Stormont Estate is the site of Northern Ireland’s main government buildings, including the Parliament Buildings, Stormont Castle and Stormont House. It was built in 1933 at a cost of nearly £1.7 million and was designed to house the newly formed Government of Northern Ireland. It was officially opened on 16 November 1932 by the then Prince of Wales, on behalf of King George V. The architect Sir Arnold Thornley designed the building with perfect symmetry and symbolism. The building is 365 ft wide representing one foot for every day of the year. It has six floors and six pillars at the entrance, one for each county in Northern Ireland. Sir Arnold Thornley was knighted by King George V in recognition of his architectural work. In March 1987 the main Parliament Building became a Grade A listed building.