Schools will be closed Monday on the iconic Greek island of Santorini after a series of 200 earthquakes shook the popular tourist destination in recent days.

Tremors between Santorini and Amorgos since Friday led to school closures in Santorini, Ios, Amorgos, and Anafi, as authorities monitor the seismic activity.

More than 200 tremors have been registered since Friday between the volcanic islands of Santorini and Amorgos, the civil protection ministry said in a statement on Sunday, citing experts tasked with assessing earthquake risks and monitoring Greece’s volcanic arc.