In this paper we present new results concerning the existence and subduction of Meso-Tethyan oceanic lithosphere in the upper mantle beneath Europe, the Mediterranean and the Middle-East. The results arise from a large scale body wave tomographic analysis of the upper mantle in this region. It is shown that much more subduction has taken place beneath the Aegean and Tyrrhenean region than was previously estimated. The Eastern Mediterranean basins are linked to the old Meso-Tethyan passive margin and may in some parts be underlain by oceanic lithosphere. We demonstrate the existence of an old northward dipping subducted slab beneath Spain and the Western Mediterranean. A large zone of suhducted oceanic lithosphere is found beneath the entire Alpine orogenic belt from Spain to Iran at depths between 250-600 km. This zone represents major parts of the Meso-Tethys.