WrestleMania is considered World Wrestling Federation's (WWF, now WWE) flagship event, having first been held in 1985. It is the longest-running professional wrestling event in history and is held annually between mid-March to mid-April. It was the first of WWF's original four pay-per-views, which includes Royal Rumble, SummerSlam, and Survivor Series, dubbed the "Big Four". It has been described as the Super Bowl of sports entertainment. WrestleMania X-Seven was the seventeenth WrestleMania event.