The Diamond Jubilee celebrates the 60 years that Queen Elizabeth II has remained Britannia's head of state.
But what has robed that royal head? A flick through the Albion albums reveals it is not just the crown that can be counted among the Queen's collection of headwear.
Diamond tiaras have sat regally atop Her Majesty on many ceremonial occasions throughout the years, but during the 50s, more close fitting bonnets were seen on state visits.
As the Queen grew more confident in her majestic mold, so her august headwear became the centrepiece of any outfit.
A yellow spaghetti design might seem a courageous choice for even the most unrestrained celebrity (Lady Gaga excepted) but it kept her Majesty's ears warm during a visit to Schoeneberg, West Berlin in May 1965.
Flowered and feathered concoctions have been favoured by Her Majesty throughout her reign, with some of her early choices revealing frothy fascinators more reminiscent of something Princess Beatrice would select.
The hippy movement of the 60s and 70s heralded flower power, and Queen Elizabeth's hat collection gave more than a nod to the trend. Mounds of daisies, styled into towering floral crowns were worn by Her Majesty during her visit to The Isle of Man in 1972.
A pink confetti-like number was worn to Royal Hospital garden party, Chelsea, in connection with the 50th anniversary of the women's services, in a trend that continued throughout the decade.
The Queen, an erstwhile lover of bold colour, made no exception when it came to choosing headwear. Sartorial choices that may have been judged unwise by some, nonetheless revealed a headstrong monarch unafraid to step with style into the limelight. And lime it was, and beetroot, and even tangerine.
Her majesty's milinery is also notable for its apt suitability to the occasion. Whilst on a visit to the opening on the Dockland's light railway, it was a naval theme, with a white and royal blue boater gracing Queen Elizabeth's head.
The royal babushka made its first appearance in the late eighties, as silken scarves replaced sturdier head covering to reveal a more casual queen. First photographed during more rural pursuits, for example whilst at the Royal Horse Show, this look became almost iconic for Queen Elizabeth, and has stayed with her well into the 21st century.
Our gracious sovereign has not shied away from flamboyant headwear as she enters her silver years either. Take a look at some of reigning shots below.