Landslides depth of 10–15 m in the river valley occurred at altitude of 315–440 m.a.s.l. Colluviums built of mixture of high plasticity saturated flysch soils and rocks were activated after rainfalls. Erosion and loading by the embankment influenced the slope instability. Few buildings, football stadium and road were located on landslides. Investigations included mapping, drillings, laboratory tests, GPR and monitoring. LEM analysis recognized low factors of safety. Partial stabilization 2007 included retaining pile walls, anchors, gabions on pile foundation, gabions along the river and surface drainage systems. Forty three sets of monitoring measurements in 9 years time detected displacements of 8.4–15.2 mm to a depth of 12–15 m. Third landslide was activated after a high precipitation in 2010. Eight buildings, road, power and water supply, telecommunication infrastructure were damaged. Remediation included retaining wall of Larsen steel elements. However, the road in severe whether conditions could be at risk. Localization of infrastructure should be based on regional planning and environmental restrictions.