The Big Two derby, also referred to simply as the Big Two or Bel Classico, is the name given to the Northern Irish association football derby between Belfast clubs, Linfield and Glentoran. The derby is also sometimes referred to as the Belfast derby. They are the two most successful and most supported clubs in Northern Irish Football. They traditionally face each other on Boxing Day each year which usually attracts the largest Irish Premiership attendance of the season. They regularly play each other in the league, and have contested more cup finals together than any other two clubs. They also make up two of the three clubs (along with Cliftonville) that have competed in every season of the Irish League's top flight since its inception in 1890 – neither club ever suffering relegation.