Originally designed and built by International Amusement Devices , the roller coaster opened as Colossus on June 29 , 1978 .
Twisted Colossus ( formerly Colossus ) is a steel roller coaster at Six Flags Magic Mountain amusement park .
Originally designed and built by International Amusement Devices , the roller coaster opened as steel roller coaster on June 29 , 1978 .
Twisted Colossus ( formerly Colossus ) is a steel roller coaster at Six Flags Magic Mountain amusement park .