Full moon concert held at National Observatory in Athens, Greece

A singer performs during a full moon concert at the National Observatory, in Hill of the Nymphs, in Athens, Greece, on June 28, 2018. The concert featuring Greek, Danish, Norwegian and French artists was organized by National Observatory of Athens in cooperation with the Danish Institute of Athens. There are many full moon concerts free of charge to people in summer time in Greece. (Xinhua/Marios Lolos)