I hadn't seen this posted yet so here it is:
Six Flags Great America celebrates with new Anniversary Pass
Available August 5
August 5, 2006 marks the official 45th Anniversary of Six Flags, the world’s largest regional theme park company. In celebration of this banner year, Six Flags has announced a new Anniversary Pass The pass is free for guests who purchase a full-price general admission ticket at any Six Flags branded theme park. Available beginning August 5th, the Pass can be used for unlimited return visits to the park for the remainder of the ‘06 season including Fright Fest.
Purchase your Six Flags Anniversary Pass at any Six Flags Great America ticket window beginning August 5.
