Lesbos, this mountainous island whose volcanic origins explain the presence of many warm springs, does not only attract visitors for its magnificent sandy beaches or the memory of the poet Sappho. For example, the preserved Byzantine fortress of Molyvos, the best preserved in the Western Mediterranean, offers sumptuous panoramas from its ramparts, while the petrified forest in the village of Sigri is a geological witness to the dense subtropical vegetation of giant conifers that covered the region 20 million years ago. Finally, the monasteries are active pilgrimage sites, particularly that of Taxiarchis (Archangel Michael), the patron saint of the island.