Last Saturday I was in Gibraltar and I was surprised to see the "Ceremony of the Keys" this used to be a daily ceremony where the gates to the garrison would be locked for protection, it is now just performed once a year.
This year it was performed by the 42nd Regiment of Foot they later amalgamated with the 73rd Regiment of foot and became the Black Watch regiment.

My 4x great grandfather Lewis GORDON (b: ABT 1804 d: 25 DEC 1877) served with the 42nd for 25 years (1821-1846) mostly In the Med and Ionian islands, He was a Quartermaster and he was pensioned off with cirrhosis of the liver.

en.wikipedia.org/wiki/42nd_Regiment_of_Foot