1. Celtic v Rangers
The "Old Firm" derby in Glasgow between The Celtic Football Club and Rangers Football Club is what I believe to be the biggest club footballing rivalry in the world. All football fans are familiar with the term "football is religion", but it is the rivalry between these two great Scottish clubs which sums up that expression the best. The rivalry is infused with a series of complex disputes centred on religion (Catholic and Protestant) and social ideologies (Conservatism and Socialism). Rangers' traditional support is largely from a Protestant community, whereas Celtic's is largely from those of Irish Roman Catholic backgrounds and it is these characteristics of the two clubs - combined with that they are the two most successful Scottish clubs and come from the same town - which makes this footballing rivalry as big and as nasty as it is. Although the rivalry is felt in majority by the fans, all those who represent the club are aware of the history of understand why Old Firm derbies are as volatile as ever. Simmering tensions between the two sets of opposing fans exploded after Celtic's 1-0 victory over Rangers in the 1980 Scottish Cup Final when an on-pitch battle raged after the final whistle. This remains one of the worst invasions onto a football pitch ever reported, and was instrumental in alcohol being banned from Scottish football grounds. The Old Firm rivalry has fuelled many assaults on Derby Day and some deaths have been attributed to the violence of post-match battles, which is obviously terrible and unacceptable, but it all adds to the rivalry. On-field it is hard to separate the two. Celtic is undoubtably the best team at present as Rangers are working their way back up to the First Division after the club went into liquidation and subsequently demoted to the Scottish Third Division. The two have 98 league titles and 69 league cups between them as Scottish football has been a two-tier system since its inception in the late 1800's. Rangers ensured immediate promotion into the Second Division after winning the Third Division for the first time in their history and will surely enough earn back-to-back promotions at the end of the 2013/14 season that will see them back in Scottish football elite and having a guaranteed two fixtures against their most hated of rivals. One can wonder whether we will see a demise in the rivalry after a few years of separation ... I'd still make sure there's enough police at the ground.