The Cașin is a right tributary of the river Trotuș in Romania.

[1][2][3] It discharges into the Trotuș in Onești.

[4] Its length is 54 km (34 mi) and its basin size is 308 km2 (119 sq mi).

[2] The following rivers are tributaries to the river Cașin (from source to mouth):[2]

This article related to a river in Bacău County is a stub.