By the 1960s, the property had become a world-renowned boxing venue, where “fighters fought in front of standing-room-only crowds in the 1,200-seat arena,” according to the documents. “The Blue came to epitomize the ideal of the Philadelphia fighter. More than 30 future champions, including Joltin’ Jeff Chandler, Harold Johnson, heavyweight Tim Witherspoon, and longtime middleweight title holder Bernard ‘The Executioner’ Hopkins, honed their skills in its ring.”