The National Constitution Center is an organization that seeks to expand awareness and understanding of the United States Constitution and operates a museum to advance those purposes. A groundbreaking ceremony for the museum was held on September 17, 2000–213 years after the original Constitution was signed. On July 4, 2003, it was opened and the National Constitution Center joined other notable sites and iconic exhibits in what has been called "America's most historical square mile" because of the proximity of historical landmarks such as Independence Hall and the Liberty Bell. Then-Supreme Court Justice Sandra Day O'Connor, officiating at the opening ceremonies, said, "It will contribute each and every day to the reinforcement of the basic principles that bind us together as a nation and a people."