Aa River

The Aa is a river in northern France that flows northward through Pas-de-Calais for approximately 89 kilometers. It originates near Bourthes village and empties into the North Sea near Gravelines.

Written records mention the river as Agnona beginning in the 7th century. Viking settlements later developed near its estuary during the medieval period.

The river shapes how local communities developed and built their settlements over time. Its presence remains woven into the identity of the region's towns and villages.

Walking and cycling paths run along the river between Saint-Omer and the coast, offering straightforward access to the waterway. Spring through autumn provides the most pleasant conditions for exploring the area.

The name comes from Old Dutch and simply means water. Local people in the Picard dialect sometimes call it Abbe, a traditional term that survives in speech today.

Location: Pas-de-Calais

GPS coordinates: 50.60690,1.93420

Latest update: December 19, 2025 22:25