One Canada Square is a prominent skyscraper located in Canary Wharf, London. Completed in 1991, it stands at 235 meters (771 feet) tall, making it the second tallest building in the United Kingdom. The building features a distinctive pyramid-shaped roof and is primarily used for office space. The tower is part of a larger development in Canary Wharf, which is known for its modern architecture and financial institutions. One Canada Square houses various companies, including banks and professional services firms, contributing to London's status as a global financial hub.