The Queen is colonel-in-chief of seven regiments, which are collectively known as the Household Regiments. Out of these, three Foot Guards regiments take it in turn to guard Buckingham Palace, whilst two Cavalry regiments guard the Horse Guards Building on Whitehall.

There has been a guardhouse on this site since 1649, but the present building dates from 1750. Only members of the Royal Family are permitted to drive through the central arch. Outside the building, two mounted guards are posted from 10am to 4pm offering a great photo opportunity for tourists.

All of these regiments take part in the daily ceremony known as the Changing of the Guard. Technically the name includes both the guards of Buckingham Palace and those at the Horse Guards Building, but in more common usage the name Changing of the Guard refers to the ceremony outside Buckingham Palace, whilst the ceremony that involves the Horse Guards is known as the Horse Guards Parade.