The Trotuș (Hungarian: Tatros) is a river in eastern Romania, a right tributary of the river Siret. It emerges from the Ciuc Mountains in the Eastern Carpathians and joins the Siret in Domnești-Sat near Adjud after passing through Comănești and Onești in Bacău County. The total length of the Trotuș from its source to its confluence with the Siret is 162 km (101 mi). Its basin area is 4,456 km (1,720 sq mi).

Towns and villages

The following towns and villages are situated along the river Trotuș, from source to mouth: Lunca de Sus, Lunca de Jos, Ghimeș-Făget, Palanca, Agăș, Comănești, Dărmănești, Târgu Ocna, Onești and Adjud.

Tributaries

The following rivers are tributaries to the Trotuș (from source to mouth):

Left: Gârbea, Valea Întunecoasă, Antaloc, Valea Rece, Bolovăniș, Tărhăuș, Șanț, Cuchiniș, Brusturoasa, Caminca, Șugura, Dracău, Agăș, Seaca, Ciungi, Asău, Urmeniș, Plopul, Larga, Cucuieți, Vâlcele, Gălian, Caraclău, Tazlău and Pârâul Mare

Right: Comiat, Bothavaș, Ugra, Boroș, Valea Capelei, Aldămaș, Popoiul, Ciugheș, Cotumba, Grohotiș, Sulța, Ciobănuș, Șopan, Uz, Dofteana, Slănic, Nicorești, Oituz, Cașin, Găureana, Gutinaș, Bogdana, Gârbovana, Căiuți, Popeni, Bâlca and Domoșița