Geotechnical investigation was carried out in three sites of the Nile Delta, Egypt for major projects. The investigations used Piezocone, Field Vane, and continuous “undisturbed” sampling to establish the stratigraphy, soil properties, and natural variability. The Deltaic deposits include silty sand and inter-layered clay, organic silt and sand. The aim of this paper is of two folds. The first one is to calibrate the existing correlations to classify the Deltaic deposits using the results of Peizocone. The second fold is to address the applicability of CPTU-undrained shear strength correlations to Deltaic clay/silt deposits. An existing CPTU-undrained shear strength correlation is updated. The data in this paper, together with published data, is used to propose a new CPTU-undrained shear strength correlation for wide ranges of plasticity index using corrected Field Vane undrained shear strength of the clay.