Assessment of landslide hazards is important in highway engineering especially considering the landslide hazards along challenging roads; more research is needed to understand progressive strategies. Therefore, multidisciplinary and advanced methodologies were needed to assess the formation mechanisms and stability of complex landslides on the Muzaffarabad-Mansehra Highway in northern Pakistan. The main study objectives were to investigate slope failures, identify the triggering mechanism of layered rocks, image subsurface geometrical configurations, and assess slope stability factors using field operations, remote-sensing tools, geomorphological mapping, geophysical imaging, and kinematics analysis. The findings indicate that the foliated Hazara Formation, being buckled easily, is particularly susceptible to the geo-environmental conditions that triggered the landslide. Geophysical surveys revealed multiple layers of varying depth and thickness, highlighting the complexity of the landslide. Low resistivity zones (0.325-1 350 Ω·m) indicated the presence of un-onsolidated, water-saturated materials and highly sheared substances, whereas high resistivity zones (1 510-26 092 Ω·m) were associated with overburden, including alluvium, boulders, and dry slate fragments. Seismic refraction tomography indicated low P-wave velocities (400-1 800 m/s) within highly saturated overburdens, reworked blocks, and surficial weathering. The subsurface layers are interspersed with fragmented pieces of high-density rock and massive boulders, displaying P-wave velocities within the range of 3 000-5 000 m/s. Both tomographic methods revealed a fracture zone extending 30 m depth, which poses a significant risk of catastrophic occurrences. The sliding surface was found to be 25-30 meters depth at the crown and 45 meters depth in the main body. Kinematic analysis identified wedge failure as the primary failure mode along highway cuts. The findings of this study demonstrate the significance of employing integrated techniques to analyze the underlying mechanics of landslide hazards within the context of highway engineering. Furthermore, these integrated procedures are highly advantageous in efficiently eliminating the associated risks posed by such hazards.