County Hall (sometimes called London County Hall) is a building in the district of Lambeth, London that was the headquarters of London County Council (LCC) and later the Greater London Council (GLC).
 
It sits on the Thames opposite the Houses of Parliament.
 
During the 1980s the then powerful Labour-controlled GLC led by Ken Livingstone was locked in conflict with the Conservative national government of Margaret Thatcher. The façade of County Hall frequently served as a billboard for opposition slogans. 
 
Eventually the government of Margaret Thatcher abolished the GLC in 1986, County Hall lost its role as the seat of London’s government. Today it’s a popular tourist destination
 
Interesting facts...
The London Dungeon, part of County Hall since 1997, reports child hauntings with sounds of scratching or cries, attributed to historical poverty and child exploitation in the area. Staff and visitors have noted eerie sensations, but these blend with the attraction’s theatrical scares rather than confirming distinct apparitions. I bet that helps to sell tickets....