Adopted in 1502; The flag of Gibraltar is comprised of two horizontal bands of white (top, double width) and red with a three-towered red castle in the center of the white band; hanging from the castle gate is a gold key centered in the red band; the design is that of Gibraltar's coat of arms granted on 10 July 1502 by King Ferdinand and Queen Isabella of Spain; the castle symbolizes Gibraltar as a fortress, while the key represents Gibraltar's strategic importance - the key to the Mediterranean. Gibraltar was ceded to Great Britain by Spain in the 1713 Treaty of Utrecht. It remains an autonomous British dependency. The UK retains responsibility for defense, foreign relations, internal security, and financial stability.

Gibraltar outdoor flags are USA made of nylon flag material and are finished with a canvas heading and two brass grommets on the hoist side, 2 rows of stitching top and bottom sides and 4 rows of stitching on the fly side. They are attached to the flagpole by means of a halyard (rope) and flag snaps, or to smaller poles with flag fasteners. Available sizes for outdoor Gibraltar flags are 2x3 ft., 3x5 ft., 4x6 ft., 5x8 ft. and 6x10 ft.