If a base is present, it should be marked in subsector maps, and the UWP. Other types of bases, e.g. army bases, merchant exploration or trade bases, and defense establishments may be indicated.
A Navy Base (code N) is an Imperial Navy facility.
A Naval Depot (code D) is a large Navy Base used to support large-scale Naval activities. There should be no more than one naval depot per sector.
A Scout Base (code S) is a Scout Service facility.
Scout Way Stations (code W) may be found at selected worlds along xBoat communication routes, and are never co-located with naval depots. They perform maintenance and repairs on xBoats.
A joint Navy and Scout Base (code A) or joint Navy Base / Scout Waystation (code B) are facilities that are co-located with each other. They may share some areas - like housing, dining and recreation - and have other areas that are exclusive or have controlled access - like stores, repair and communications.
A Military Base (code M) is an Imperial Army or Imperial Marines facility. If co-located with a Navy and / or Scout facility then it is considered subordinate to them and uses their classification instead.