Mattock River

The Mattock River is a river in Ireland. It is a tributary of the River Boyne. Its source is near Collon (53.775°N 6.495°W / 53.775, 6.495), from where it flows through County Louth towards the southeast until a place west of Drummond Tower in Coolfore where it begins to form the boundary between Counties Meath and Louth. Here it turns towards the southwest until Monknewtown where it takes a southeastern direction again before turning roughly east at Dowth. It joins the River Boyne at Oldbridge in the parish of Drogheda (53.7207°N 6.4276°W / 53.7207, 6.4276). The estimated terrain elevation above sea level is 10 metres.

Flows through: Ireland.

River data from Wikidata (CC0); lengths normalised to a common unit.