Abstract: The western Mediterranean region contains abundant examples of the different types of Lower, Middle and Upper Miocene reefs (hermatypic coral reefs, ahermatypic mounds, rhodalgal biostromes and stromatolitic reefs). Those corresponding to the Upper Tortonian-Messinian rock units are the ones that have attracted the most attention because of the extraordinary quality of the outcrops and their relation to the polemic Messinian events in the Mediterranean. This section is a general introduction to the region, with a review of the Lower-Middle Miocene rhodalgal biostromes and coral reefs of the Gulf of Valencia-Provençal Basin and the Middle-Upper Miocene reefs of southeastern Spain and northern Morocco. The emphasis in this paper will be on the complex Miocene stratigraphy and paleogeography of southeastern Spain (Betics) and northern Morocco (Rif). This part of the western Mediterranean is important in understanding the paleogeographic evolution of the entire Mediterranean and its connection with the Atlantic Ocean.