The series runs multiple classes of grand tourer cars in events around Spain and Portugal.

Each event consists of two races of equal distance, one run on Saturday and the other on Sunday.

A new GTS class was introduced in 2005, initially for the custom-built SEAT Toledo GT, but was adapted in 2006 to use cars from the FIA GT3 European Championship, originally without scoring points in the first year.

In the current format, the GTA class is dominated by the Ferrari F430 GT2, Porsche 911 GT3-RSR, Mosler MT900R, and the custom-built Sun Red SR21.

GTS uses GT3 versions of the Ferrari F430, Porsche 911, Lamborghini Gallardo and Dodge Viper Competition Coupe.