The following arenas are unlocked in the corresponding chapters of the Attitude Era mode on any difficulty setting:

ARENA - CHAPTER
Attitude Era Backstage - 'Mankind' chapter.
Badd Blood '97 - 'Rise Of DX' chapter.
Breakdown '98 - 'Brothers Of Destruction' chapter.
Halftime Heat Empty - 'Mankind' chapter.
Judgment Day '98 - 'Brothers Of Destruction' chapter.
King Of The Ring '98 - 'Brothers Of Destruction' chapter.
One Night Only '97 - 'Rise Of DX' chapter.
Over the Edge '98 - 'Austin 3:16' chapter.
Raw '98 - 'The Great One' chapter.
Rock Bottom '98 - 'Mankind' chapter.
Royal Rumble '98 - 'Austin 3:16' chapter.
Royal Rumble '99 - 'Mankind' chapter.
SmackDown '99 - 'Off Script' chapter.
St. Valentine's Day Massacre '99 - 'WrestleMania XV' chapter.
SummerSlam '97 - 'WrestleMania XV' chapter.
SummerSlam '98 - 'Brothers Of Destruction' chapter.
Sunday Night Heat - 'Off Script' chapter.
Survivor Series '97 - 'Rise Of DX' chapter.
Survivor Series '98 - 'The Great One' chapter.
Unforgiven '98 - 'Austin 3:16' chapter.
WrestleMania XIV - 'Austin 3:16' chapter.
WrestleMania XV Arena - 'WrestleMania XV' chapter.