Location of the four Sen3Exp campaign test sites marked on MERIS images that were acquired during the campaign window. Ground measurements, airborne data and satellite images were taken of Barrax in Spain, San Rossore in Italy, Boussole ocean buoy in the Ligurian Sea and the Acqua Alta Oceanographic Tower (AAOT) in the Adriatic Sea. The image shows the location of the sites and two MERIS images taken during the campaign.