Gironde
The Gironde is often falsely referred to as a river but it is in fact a navigable estuary in southwest France. It is formed from the meeting of the rivers Dordogne and Garonne just downstream of the centre of Bordeaux. Covering around 635 km2, it is the largest estuary in western Europe.
The Gironde is approximately 80 km long and 3–11 km wide, it is subject to very strong tidal currents and great care is needed when navigating the estuary by any size or type of boat.