During a 3 year sand-dune regeneration project in the Laida beach (Biosphere Reserve of Urdaibai) both dune formation process and sedimentary features have been monitorized. The measured bimodal wind regime controls both the formation of bipolar sedimentary structures at different scales and the growth of the sand dune. Main depositional and erosiona! processes controlling sand dune development and the preserved internal sedimentary structures are shown in this pape
