The Bathurst 12 Hour, currently known as the Repco Bathurst 12 Hour for sponsorship reasons, is an annual endurance race for GT and production cars held at the Mount Panorama Circuit, in Bathurst, Australia. The race was first held in 1991 for Series Production cars and moved to Sydney's Eastern Creek Raceway in 1995 before being discontinued. The race was revived in 2007, again for production cars, before adding a new class for GT3 and other GT cars in 2011. This has led to unprecedented domestic and international exposure for the event. In all, twenty one races have taken place; twenty at Mount Panorama and one at Eastern Creek Raceway.

Group GT3, known technically as Cup Grand Touring Cars and commonly referred to as simply GT3, is a set of regulations maintained by the Fédération Internationale de l'Automobile (FIA) for grand tourer racing cars designed for use in various auto racing series throughout the world. The GT3 category was initially created in 2005 by the SRO Group as a third rung in the ladder of grand touring motorsport, below the Group GT1 and Group GT2 categories which were utilized in the SRO's FIA GT Championship, and launched its own series in 2006 called the FIA GT3 European Championship. Since then, Group GT3 has expanded to become the de facto category for many national and international grand touring series, although some series modify the ruleset from the FIA standard. By 2013, nearly 20 automobile manufacturers have built or been represented with GT3 machines.