Lesvos is donated with an impressive hydrographic network due to the climatic conditions, rainfall, geological formations and active tectonics.
Thus Lesvos hosts impressive gorges, valleys and waterfalls which are scattered throughout the island. They are sites of aesthetic value but also important ecological hot spots.
Along the riverbeds appear steep waterfalls which are usually associated with the presence of active faults. Impressive waterfalls appear such as the Man’ katsa formed in the ignimbrite rocks close to Mandamados, the Pessa waterfalls in Achladeri crossing the ophiolitic rocks and stemming from the small Lake and Mount Olympus, the Klapados waterfalls, the Parakoila waterfalls, the Vathylimnos waterfalls in Chidira, the water falls in the stream Methalia in western Lesvos, the Nigida waterfalls in Vrisa.
Man’ Katsa Waterfall
Pessa’s waterfall, which has a height of 15m, has been created in the Makri stream that crosses the ophiolitic rocks and stems from the small Lake and Mount Olympus. The steep cliffs of the waterfall interrupt suddenly the flow of the stream “Kryo Nero” (“Cold Water”). They were created by a fault which crosses the ophiolitic rocks.
Man' Katsa Waterfall
The Man’ katsa waterfall can be found in the Aspropotamos river near the settlement of Pedi. The river sweeps over the edge of a cliff and falls for 15m into a pool. The waterfall was formed when a large fault cut through the ignimbrite rocks and the Aspropotamos river bed, thus creating an impressive cataract of water.
The ignimbrite rocks were formed 17 million years ago by a particularly violent eruption of the Lepetymnos volcano. The eruption caused the expulsion of hot gases along with fragments of pumice, glass, lava droplets and other pyroclastic material which, due to its fluid state, covered the ground and bonded to it. Ignimbrite lava formed flows which covered older volcanic rock land formations. The succeeding tectonic activity and the erosion of the rock created the remarkable landscape we see today.
Voulgaris Gorge (Vatoussa)
The gorge of Voulgaris River is an impressive gorge created on the northwest side of the volcanic crater of Vatoussa, a huge volcano with a diameter of more than 8.5km.
The gorge of Voulgaris was formed in volcanic rocks due to the water erosion along the traces of large geological fractures. It is a deep ravine with almost steep rocky sides.
The gorge is developed on volcanic conglomerates formed by the the collapse of the northern side of the Vatoussa volcano and are witnesses to the violence of the volcanic activity. The collapse of part of the volcano released a lava stream which compacted in its passage parts of the already solidified lava created from earlier activity of the volcano.
Tsiknias River Valley
Tsiknias river, which crosses the central part of the island, concentrates waters from the southern flanks of Lepetymnos mountain and flows into the Gulf of Kalloni. The hydrographic network of Tsiknias is developed on the Miocene volcanic formations of Lepetymnos and is largely affected by active tectonics.
Tsiknias basin is one of the largest river basins on Lesvos. The water catchment area of the Tsiknias torrent is developed on Miocene volcanic rocks of the Lepetymnos mountain, which is the largest volcanic center on Lesvos.
Thiknias river forms also extended marshes and wetlands along its delta which is one of the most important ecotopes for the migratory birds. Alluvial fans and torrent deposits (clays, sands, fluvial deposits) exist mainly around the mouth of the river.
Surfice raptures appear along the Tsiknias river bed after the 1967 strong earthquake in Central Lesvos, visible from the river mouth in Kalloni bay till the village of Agia Paraskevi.
The Tsiknias River gorge was formed in the southern slopes of the ancient Arisvi hill. Water action carved out the gorge on the volcanic rocks along the traces of major geological faults with NW – SE and NE – SW orientations.
To the east of the village of Petra the valley of Ligona spreads formed on Miocenic volcanic formations of the western flanks of Lepetymnos.
It is a beautiful valley with impressive lava flows and columnar lavas. Within the valley of Ligona, the ruins of 17 watermills of the 19th century are located in a row, the last phase of the history of watering. Watermills, remarkable architectural elements of pre-industrial period, are an integral part of the local economic and social history of the island, connected with significant economic activity, the production of the region and the everyday life of the inhabitants.