The Glennagannon River flows through County Donegal in Ireland's northwest, draining toward Trawbreaga Bay near the Inishowen Peninsula. This relatively modest river holds both resident juvenile brown trout and Atlantic salmon, and its estuary mouth opens onto productive coastal waters where sea trout are a prized target. The river and its surrounding estuary represent a classic piece of Irish northwest coastal fishing, combining freshwater and saltwater opportunities within a short stretch of shoreline.