## 5 Conclusions  
This study provided a practical example in verifying the effectiveness of landslide engineering remedial works and the geomorphological stability characterization of landslides employing an InSAR and conventional ground monitoring combined method. To this aim, the effectiveness of InSAR-based techniques was exploited at the regional scale to determine possible hot spots of landslide hazards. The matching with landslide inventories allowed us to downscale the analysis to the slope scale where possible precursory signals of instability were identified. At this scale, where deemed necessary, more detailed analyses were conducted: Field surveys and conventional ground monitoring data had the irreplaceable advantages in obtaining substantial insights for each hotspot, including deformation mechanisms and the inducing factors.  
The results correspond to the field evidence and matched with the outcomes of previous research in this area. Compared to previous studies, the effect of geohazard engineering remedial works was emphasized and taken as a primary consideration. The multi scale analysis allowed us to detect precursory signals of possible instability in certain sections of the controlled landslides. In general, with a total of 310 mapped landslides, 52 of them (13.87%) were classified as active in a slow-moving state. A total of 58 landslides were instrumented (18.71%), and others were slowed through remedial efforts. We found two controlled landslides that were confirmed to be active, while another nine cases were suspected to be active and demand further attention.  
Currently, extensive protective measures have been planned and carried out; however, it is not feasible to avoid all threats or protect all affected areas. Considering that we cannot prevent all landslides and landslide remedial work could have been weakened or even failed, different strategies involving monitoring and early-warning systems are valid options for risk mitigation. This strategy relies on satellite InSAR, starting from the most urgent situations, combining advanced techniques with practical experience. This could not only greatly reduce the effort of field work but also effectively identify potentially dangerous landslides. The proposed procedure is low-cost, easy to perform and very straightforward to communicate to citizens and authorities. It could be easily implemented on very wide areas to assess the slope stability and to investigate the effectiveness of large-scale governmental risk mitigation programs, identifying precursor signals that could allow for intervention before reaching critical conditions.  
Conceptualization, S.L.; methodology, S.L.; investigation, S.L., C.Z., and Y.Z.; data curation, S.L. and Y.Z.; writing--original draft preparation, S.L. and S.S.; writing--review and editing, S.S., F.R., C.Z., and K.Y.; supervision, K.Y. and N.C.; funding acquisition, K.Y. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the National Key R&D Program of China (No.292 2018 YFC0809400).  
We greatly appreciate the support from [PERSON] and [PERSON] for providing data and material. We also thank the editor and anonymous referees for their comments and contributions.  
The authors declare no conflict of interest.