Fort Risban, Fort at the port entrance of Calais, France.

Fort Risban sits at the harbor entrance of Calais with thick stone walls built to control ships entering and leaving the port. The structure includes multiple bastions and fortified sections added during different periods of construction and renovation.

English forces constructed an initial wooden fortification in 1346 to cut off supply lines during their lengthy siege of the city. Over centuries, the structure was rebuilt and reinforced by different powers that controlled the territory.

English accounts called it Risbanke or Risbank, and after 1400 the stone tower was renamed Lancaster Tower, a name often applied to the whole fort. The site passed between England, Spain and France, and its fabric shows successive military building methods.

The fort is located along Avenue Raymond Poincaré and easily accessible from the harbor and waterfront areas of Calais. Walking paths connect the site to the port district and offer views from various angles along the walls.

Vauban inspected Fort Risban in the 1680s, not 1680, and judged it "a home for owls, and place to hold the Sabbath" rather than a fortification; he then had the fortress altered. The remark survives as the fort's best-known description, recorded in accounts of his tours of the northern coast.