A letter - handwritten by the Queen before her death - is currently being held in a vault in Australia with strict instructions not to open it until 2085.
The letter is addressed to the people of Sydney and is kept in the city's historic Queen Victoria Building.The Queen wrote the letter when the building had been fully restored in 1986 and now sits in a glass case inside a restricted area in its dome.
It's said that not even her personal staff know what the letter contains and all that can be seen is who the letter is addressed to and the Queen’s strict instructions as to when the letter can be read.
The letter – which is signed by the Queen herself - is addressed to the "Right and Honourable Lord Mayor of Sydney, Australia".
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