Geophysical and geotechnical data have been collated over the years from various sites in the Aegean Sea for the purpose of demarcating safe routes for submarine cables between mainland Greece and non-interconnected islands. Geodatabases have been developed for the assessment of cable burial, which includes piezocone tests (CPTu), vibro-cores and high-frequency (3.5 kHz) shallow seismic profiles. A comprehensive geodatabase has been constructed to provide discrete qualitative classifications of acoustic response, based on calibrated CPTu and vibro-core data, from three sites (Evia-Skiathos, Lavrio-Evia and Lavrio-Agios Georgios). Classification is initially based on CPTu, according to basic parameters (qt, u2, fs and Rf), followed by additional CPTu information (SBT charts, Su, etc.) and vibro-core analysis. Four main acoustic groups have been identified across the three sites. The first group exhibits facies of low amplitude to transparent reflection with some level of faint-to-moderate layering at deeper sections. qt exhibits values between 0 and 5 MPa, along with positive pore pressures, consisting of cohesive sediments of high-to-medium plasticity to silty sands. The second and third group display high-amplitude surficial reflectors with restricted penetration and represent intermediary CPTu response, with qt of 5-10 MPa and 10-20 MPa, respectively. Pore pressure is either variable or close to pressure equilibrium, with sediments consisting mainly of silty sands to sands. The fourth group shows high qt values (≥20 MPa) that correspond to coarser lithology (sands/silty sands to gravel) and harder substrates, with some CPTu tests exhibiting refusal, with a varied to negative pore pressure. Seismic facies show high-amplitude chaotic reflection, with occasional patches of medium-amplitude reflection. Results from the seismic facies–geotechnical correlation offer insights into the geological and geotechnical factors affecting CPTu and by extension the acoustic response of shallow stratigraphy.