Által-ér is a right tributary of the Danube in Komárom-Esztergom county. The watercourse of the eastern edge of the Kisalföld, collects the waters of the NW side of the Vértes mountain range, originates south of the village of Császár, west of Pusztavám, at an altitude of about 140 meters above sea level, then bypasses Pusztavám and takes its way to the northeast. The water flow passes through the Bokodi cooling lake, at Tatabánya it turns to the NW at the fault line of the Tatai ditch. It passes through the middle of the Öreg Lake in Tata and reaches the Danube at Dunaalmás in a wide valley through five drains. A part of the water of the main branch flows into the Mikoviny channel, the main branch merges with smaller streams from the right and flows into the Danube. Watercourses: Egerárki River, Szépvíz River, Fekete River (or Gerencsér River), Büdös River, Pénzes Stream, Labanc Stream, Majki Stream, Gesztesi Stream, Galla Stream, Árendás Stream, Mihályi Stream stream, Csákány stream (It was also called Rákos stream during the time of the conquest and the Middle Ages.)
Tourism
The Által-ér valley cycling route between Dunaalmás and Tata
In the Által-ér valley, a cycling route was developed in several phases in the 2010s. The 6.8 km section between Tatabánya and Tata (with Vértesszőlős connection) was handed over at the end of 2013, followed by the 8 km section between Tata and Dunaalmás which was handed over in 2015, reaching the planned route of the EuroVelo 6 Danube cycle path.[3] In 2019, the 11 km cycling route connecting Tatabánya with Oroszlány via Kecskéd and Környé was completed, which is also connected by an unpaved branch to the Majki Kamaldul hermitage.