This unique isolated watchtower, known as the “Tour Carbonnière” (Carbonniere Tower) was once a crucial line of defense. It was built in the 13th century for the nearby town of Aigues-Mortes in southern France. At the time, the fortress was the “key to the kingdom” in the region.

The tower stands in the middle of a salt marsh and the road to the town led directly through the tower. Travelers approaching Aigues-Mortes had to pass through the tower’s archway, a portcullis, and a small garrison of men, whose job was to guard the town, the road, and the tower itself. In addition, those using the road were required to pay a toll to pass through the gate.

Eventually the defense of the tower was abandoned and it became a relic of a bygone era, although the road was still used. Into the 1700s, the tower itself still served as a tollbooth, charging travelers who drove on the road that passed through its gates. Eventually, roads were built to curve around the tower, as its gate was too small to accommodate larger vehicles.

The Carbonniere Tower has been classified as a historical monument since 1889. It was restored in the 19th century (in part for safety reasons) and still stands sentinel over the surrounding swampland. The structure is now a tourist site which can be visited by anyone driving by and willing to stop. It might not be defending anything any longer, but it is nevertheless a fascinating bit of medieval construction.

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