Peat, recognized for its intricate soil composition, showcases significant challenges in terms of construction, resulting in failure of pavements, earthen embankments, damage of crucial lifeline infrastructures etc. Thus, geotechnical characterization is of utmost importance, especially in regions like northeastern (NE) India, due to a lack of comprehensive data. In this regard, the present study focuses on the NE Indian city of Silchar, Assam (India), which has significant peat deposits. Investigation in the form of both in situ and laboratory tests were conducted which included both invasive and non-invasive tests. Lithological subsoil profiles were assessed by non-invasive tests, electrical resistivity tests (ERT), and multi-channel analysis of surface waves (MASW), whereas invasive tests included standard penetration test (SPT). Samples in both disturbed and undisturbed soil samples were extracted from the Elanpur tea estate (ETE) site of Silchar, Assam. Collected samples were undergone detailed laboratory tests assessing physical, microstructural, and mineralogical parameters. Apart from that strength and settlement behavior was also evaluated, since peat showcases very low strength (cohesion), elevated pore water pressure (PWP) development and significantly high values of settlement (primary, secondary and tertiary) with values ranging from 4 to 14 kN/m2, 55 to 155 kN/m2, 2.03 to 3.68 (primary), 0.0654 to 0.3221 (secondary). A numerical validation study was also carried out in order to validate laboratory test results with numerical values showcasing 18.68% variation, along with the development of site-specific empirical equations. Thus, results derived from the present study significantly contribute to understanding the complex behavior of peat, integrating both in situ and laboratory-based analyses.