During the period represented by the sandy infills of the eastern flank caves and the Catalan Sand formation, it was likely that Gibraltar was part of the mainland, including a broad coastal plain covered with transgressive wind-blown dunes. All aeolian formations originated on marine beaches, from 6 m a.s.l. to 100 m b.s.l., before being blown inland to accumulate as topographic dunes. CUff-front aeolian accumulations comprise echo dunes, climbing dunes and sand ramps. Aeolian deposition began immediately before the last interglacial marine highstand (MIS 6-5 transition) and continued during the subsequent fall in sea level until the end ofMIS 3