Her Majesty's tiaras are at the heart of her jewellery collection, so extensive it has to be stored in a room the size of an ice rink, 40ft below Buckingham Palace.
From priceless diamond bands to headpieces laden with precious stones, they are the crowning pieces of her wardrobe, each carefully selected for the occasion and worn with effortless elegance.
A favourite of the Queen mother
Resplendent in rubies, this Oriental circlet tiara was designed by Prince Albert for his new wife Queen Victoria, for £860 (equivalent to about £76,000 today) in 1853. The headpiece is huge, containing more than 2,600 diamonds and 11 rubies.
Gift for a youthful bride
The tiara, which cost £5,000 in 1947 (equivalent to £189,000 today), was set with 1,033 diamonds and had three detachable roseshaped brooches. It was a wedding present from an Indian monarch.
The Queen's sapphire collection includes a necklace, bracelet, earrings and three rings. This, the George VI sapphire tiara, was added to the set in 1963. It began life as a necklace, bought for Princess Louise of Belgium in the late 19th century, who was a scandalous figure with a string of lovers.
Inspired by the court of the Tsars
The Kokoshnik tiara consists of 488 diamonds, set in white and yellow gold. It was presented to Alexandra, Princess of Wales, as a 25th wedding anniversary gift in 1888 - and cost £4,400 (equivalent to roughly £400,000 today). The tiara was inspired by and named after a traditional Russian headdress - Alexandra was the sister of Maria Feodorovna, Empress of Russia and wife of Tsar Alexander III.
Ruby rose style she chose for herself
This Burmese ruby tiara was commissioned by the Queen from Garrard in 1973. It's one of only a few pieces of jewellery she hasn't inherited, so the tiara is thought to reflect her personal style.
The only one that's King size
The oldest tiara - the Diamond Diadem - has been passed down from monarch to monarch since George IV's coronation in 1821. It's unique in the Queen's collection in that it was made to fit a man, and is consequently heavier than most.
Familiar? It's on the money
At the tender age of 27, the Queen wears her favourite Girls of Great Britain and Ireland tiara, at the foot of the small staircase inside Buckingham Palace in 1953. If the tiara looks familiar, it's because the Queen is pictured wearing it on our coins and banknotes.
Cool and calm in ice blue
This Brazilian Aquamarine tiara is a favourite of the Queen's dresser, who describes it as "majestic in appearance but cool and calming."
Smuggled out of Soviet Russia by a real-life James Bond
Spies, intrigue and a daring escape - the Grand Duchess Vladimir tiara has perhaps the most fascinating story of all. The Queen inherited it from her grandmother in 1953.
A headache for Diana
The Cambridge Lover's Knot tiara was said to be a favourite of Diana, despite her complaints that it was heavy, noisy - all those swinging pearls - and gave her headaches. It was commissioned by Queen Mary, and then passed to the Queen, who wore it regularly early in her reign before giving it to Diana as a wedding present in 1981.
Tiara snapped on her wedding day
As a young bride in 1947, Princess Elizabeth paired Queen Mary's Fringe tiara with her flowing Norman Hartnell gown. But it was very nearly a source of embarrassment. Just before she left for Westminster Abbey, the tiara snapped, and the court jeweller had to rush in for emergency repairs.