In this paper, the authors report on the results of the use of Landsat ETM data and IKONOS-2 high-resolution data to estimate the area of crops cultivated in the hydrological basin of Pinios River at Elia, North West part of Peloponnesus, Greece. Although Landsat ETM data provide an acceptable base-map for crop extraction and mapping they cannot be used at field level especially, where the agricultural land is fragmented with mixed and multiple crop types. IKONOS-2 pan-sharpened data generated high resolution products such as crop thematic maps depicting the crop areas with a considerable accuracy of ± 2 meters. This field based mapping level allowed a better estimation of the water needs for each crop type to be applied at each farm.