Instable rock compartments at the 1000 m high Maïdo rampart threaten the few dozen inhabitants of the islet of Roche Plate in Mafate located downslope, as well as the cliff top which is the second most popular touristic site of La Réunion Island (>500 000 tourists/year). These rock compartments of a few tens of m3 to several hundred thousand m3 are pre-cut by fractures subparallel to the cliff as far as hundred meters from the cliff edge. In November 2020, reports of crack openings after an important bush fire raised fears of the imminent collapse of several hundred m3. The stability of other rock compartments was also considered worrying. In order to assess the stability of these compartments, a permanent multiscale and partly automated system was installed to survey crack openings and surface deformations. This set up was completed by a seismic noise survey designed to qualify the degree of individualization of rock compartments. Finally, a muon tomography survey of the upper part of the rampart was deployed to image the extension of crack roots. The acquired data should make it possible to better understand rupture processes and kinetics, helping in characterizing and managing rockfall hazard at this site.