Venice, the enchanting Italian city built on a lagoonal environment, faces ongoing geotechnical challenges due to natural processes and anthropogenic influences. Over the past century, extensive geotechnical investigations have been conducted to characterize the unique stratigraphy of Venice's soils. Some key locations, representative of the city's diverse soil profiles, have undergone in-depth analysis, with investigations reaching depths of tens of meters. Three key sites—Malamocco, Treporti, and La Grisa—were strategically selected to study the complex mechanical properties of Venetian soils. In this study, we present a comprehensive synthesis of the most significant findings from the geotechnical investigations conducted throughout the Venetian lagoon over recent decades, focusing on methodologies for the evaluation of stiffness parameters in highly heterogeneous soil layers. These results enhance the understanding of geological and geotechnical behaviour of Venice's subsoil and provide crucial data for developing resilient engineering solutions.