Workers clear the area around petrified tree trunks in the Petrified Forest near Sigri village, Lesvos island, Greece on Oct. 20, 2018. The entire Lesvos island in the northeastern Aegean Sea has been designated as one of the 140 UNESCO Global Geoparks worldwide on account of its outstanding geological, cultural and ecological heritage and efforts to preserve and promote it over the past three decades. (Xinhua/Marios Lolos)