Marine fenders are used at ports and docks on quay walls and other berthing structures. Cruise ship operations benefit from faster berthing and non-anchored "moorings" off beaches or inaccessible ports. Docking and berthing of spacecraft is the joining of two space vehicles. The ESA's International Berthing and Docking Mechanism is their IDSS compatible docking system. The program envisioned the construction of four CRV vehicles and two berthing/docking modules. Each vessel has 104 permanent berthing spaces. The port of Sittwe will undergo extensive dredging and the construction of new berthing terminals. Androgynous docking (and later androgynous berthing) by contrast has an identical interface on both spacecraft. Naval vessels have been allocated 45 days of berthing per year. Berthing facilities are available at the Caudan Waterfront. The base will have submarine berthing and aviation facilities. It was a sheltered cove good for berthing seacraft. There were (measured linearly) of ship berthing space. Burning fuel poured through the hole in the deck into occupied berthing compartments below. In the 1920s several major berthing facilities were built.