The Tower of London is guarded by the Queen's Guard as it is an official royal residence. Also the army has responsibility for protecting the Crown Jewels. We did not know it at this time but after a visit to the museum of the Queen's Guard we would learn to identify the various units by the number of buttons in a cluster. On this soldier there are clusters of two meaning he belongs to the second unit to be named to the Queen's Guard - or Her Majesty's Coldstream Regiment of Foot Guards.
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