Cologne - As Borussia Dortmund prepare for their match against Ruhr district neighbours and great traditional rivals FC Schalke 04on Matchday 23, bundesliga.com has some background information for you on the German game's ultimate local power struggle.
It may not have quite the international prestige of its counterparts in, say, Manchester or Milan, but it undoubtedly carries the same weight with the hardcore fans of both clubs - and means more to them than any other fixture on the football calendar.
A Revierderby refers generally to a neighbourly meeting of two clubs from the heavily industrialised Ruhr district. More specifically, the Revierderby narrows that down to the 20 miles separating Dortmund from Schalke's home base of Gelsenkirchen. A number of other professional teams hail from the wider region, but they have to make do with the tag 'minor Ruhr derby' for their various head-to-heads.
Other than their proximity, there was no particular trigger for a rivalry which, if anything, has only intensified over the years for two sets of fans who basically like nothing more than to give each other a good pasting.
Die-hard fan base
While they might not necessarily like to admit it, Dortmund and Schalke actually have a lot in common: geography, obviously, but also roots in the coal and steel industries and a striking similarity of their fan bases.
Indeed, a predominantly working-class demographic defines the bulk of the support of both clubs. Dortmund's Signal Iduna Park boasts a higher capacity than the Veltins Arena, but Schalke's membership numbers comfortably outstrip those of their Schwarz-Gelben neighbours.
Die Knappen's pre-WWII dominance of Dortmund planted the seed for future Ruhr bragging rights, with the pendulum swinging from one side to the other ever since. In 1997, Schalke lifted the UEFA Cup, only to be trumped by Dortmund's Champions League success a week later.
Ten years down the line, Dortmund would have the last word, too, beating their great rivals on the penultimate matchday of the 2006-07 season and effectively denying them a first Bundesliga title. In the spirit of true Schadenfreude style, replica shirts commemorating the occasion were soon selling like hot cakes among the BVB faithful.
And just in case you needed any further convincing of what's at stake here, it may be worth noting the infamous response of BVB home boy Kevin Großkreutz when asked what he would do if he had a son who chose to support Schalke. The answer? Adoption...
Find out more about the mother of all derbies on the Bundesliga's official YouTube channel: