Sprouting on the west side of Lesbos are hundreds of fossilised tree trunks from a forest 20 million years old.

Some also sit underwater off the coast, but the highest density of trees can be found in a 15-hectare National Forest park between the villages of Eressos and Sigri.

The petrifaction was created by lava and ash from eruptions in the Neogene Period, and in places this volcanic material has disappeared, leaving the trunks behind.