The Gherkin is 590 ft (180m) tall, making it the 2nd tallest building in London, after Tower 42. The building is famous for its daring architecture by Pritzker-prize winner Sir Norman Foster and ex-partner Ken Shuttleworth. Its design won the prestigious RIBA Stirling Prize for the best new building by a RIBA architect in 2004. In September 2004, during London's Open House Day crowds waited for over 5 hours to get their moment up in a special visitors' area on the 40th floor. This set the record for the most people ever to visit a site on an Open House Day.