Geotechnical investigation is a systematic process of evaluating soil, rock, and groundwater conditions below the ground surface. It is typically conducted to assess the feasibility, design, and construction requirements of civil engineering projects such as buildings, roads, bridges, dams, and tunnels. The investigation involves sampling, testing, and analyzing soil and rock properties to understand their strength, composition, permeability, and other relevant characteristics. The data gathered from geotechnical investigations help engineers and planners make informed decisions regarding foundation design, earthworks, slope stability, and overall project feasibility and safety.