Sea-floor bathymetric and backscatter data is used to image one of the youngest major landslides in the Northwestern Mediterranean Sea. The landslide, a 26 km3 debris flow, covers 2,000 km2 of the Ebro continental slope and base-of-slope offshore Spain. A pattern of low backscatter large sediment blocks which moved downlope while keeping their internal coherence separated by topographically low high backscatter lineations of coarse sediment is shown in the sea-floor images. The results of the interpretation of these features provide fundamental insights on the behaviour of submarine debris flows from which hydrocarbon search could greatly benefit.