“…Distributed optical fiber sensors (DOFS) have been satisfactorily used to detect and monitor various types of ground instability phenomena such as landslides (Zhao et al, 2021), seepagerelated piping (Inaudi, 2014), or subsidence induced by tunneling (Asaf et al, 2014, Xin et al, 2021 or mining (Naruse et al, 2007). These methods have also been tested for sinkhole monitoring via physical laboratory models and numerical simulations, but to our knowledge no case studies showing the practicality of the technique in active sinkholes under natural conditions have been published (see review below).…”