Duchess Kate visits Bletchley Park in Alexander McQueen
A 3 year-old Kate wearing bright stripes.
An adorable Kate smiles at the camera, age five.
Kate with sister Pippa and Father Michael in Jerash, Jordan. The Middleton Family moved to Amman, Jordan for two and a half years.
Kate skis in the Klosters with William and family.
Kate attends the wedding of a friend, wearing a lace-patterned black and white skirt with a complimentary jacket and fascinator.
Kate at her graduation from St. Andrews, where she met Prince William.
Kate Middleton and Prince William on the day of their graduation ceremony at St. Andrews University.
A casual Kate out and about with her father, graduation weekend.
Kate, dressed in a casual sweater with a brown jacket, wore her hair up for the Gatcombe Horse Trials.
Kate and her mother, Carole Middleton, attended the Spirit of Christmas Shopping Festival in London, Kate wearing jeans and a light blue blazer.
Kate wore flat boots, a long coat and Russian-style fur hat at the Cheltenham Festival with her sister Pippa.
Wills made Kate laugh after she and her sister watched him play in a field game at Eton College.
Kate looked lovely in a long cream coat and fancy fascinator at a friend's wedding.
Kate attended the Boodles Boxing Ball, dressed in bright blue to support the sports charity Sparks.
Kate wore a floral dress and pink jacket to a store opening, letting her bangs fall to a fringe.
Kate wore red and white polka dots to the Chakravarty Polo match, completing the look with strappy wedges and classic sunglasses.
Kate dances with a friend at a pre-Wimbledon party, dressed in a dark floral dress.
Kate wore one of her favorite silhouettes, a simple wrap dress, for a Polo match.
Dressed in casual summer whites, Kate attended the Rundle Cup Day with Chelsy Davy (Prince Harry's former girlfriend) and William's cousin Zara Phillips.
Kate rocked white jeans and a simple cardigan at the Beaufort Polo Club.
Kate wore a red Armani coat to the Sovereign's Parade at the Royal Military Academy.
Kate wore this casual black and white patterned dress, arriving home from work.
Showing off some not-often-seen skin, the now Duchess was out on the town with friends.
Seen leaving the venue Boujis, Kate looked classic in a shimmering black jacket.
Back to her classic, almost professional, duds, Kate wore a matching deep green skirt and coat to the Cheltenham Festival.
For the next day of the festival, Kate went for a mix of blues and browns, wrapping it up with a pretty scarf and beret.
Kate and Pippa watched William play rugby in casual jeans and boots.
Kate wore a 60s-inspired dress out and about in London.
Kate wore a sweater and pencil skirt with boots to the Badminton Horse Trials, mastering that transitional time when Spring has a chill in the air.
The Middleton sisters looked lovely at a book launch party in London.
Kate smiles in a casual top and jeans in London.
Kate attended the Concert for Diana in London, wearing a white trench and black heeled boots.
Looking nautical in stripes and wedges, Kate was spotted in London.
Sporty-chic Kate took part in a training session with the Sisterhood Cross Channel rowing team.
Wearing a vest over long sleeves, Kate and the rowing team practice for the Charity Boat Challenge.
Kate attended another book launch, dressed in a simple cap-sleeved dress.
Kate attended an afterparty following the opening night of Afrika Afrika, wearing an animal print dress.
We love that Kate paired navy blue with black -- a look that the fashion-savvy know is super chic, but many would be afraid to do.
Kate with Prince William after his graduation, now a Royal Air Force pilot, wearing a pretty peacoat.
Kate in her go-to casual look: jeans and a jacket.
Kate attended the Most Noble Order of the Garter service, standing with Camilla, Duchess of Cornwall in contrasting black and white.
Always there to support, Kate watched Wills and Harry play in a charity polo match.
Kate wore a pretty white Issa sundress with a cardigan to the Wimbledon tennis championships.
Kate looked lovely at Lady Rose Windsor's wedding, wearing a pop of color and print with black accessories.
Kate channeled the '60s in this mod-inspired dress while out in London.
Kate attended the Day-Glo Midnight Roller Disco in London, supporting an Oxford charity.
Kate wore skinny jeans and a leather jacket to a charity Polo match in which Prince William and Harry were playing.
Kate wore a stunning blue patterned Jane Troughton coat to a friend's wedding, paired with a Jane Corbett fascinator and black court shoes.
Kate chose a belted teal sundress and leather bag for the Chakravarty Cup Polo Match.
Kate and Wills attend a friend's wedding, Kate wearing a bright silk dress with a black jacket and accessories.
A royal engagement! Kate's navy Issa dress from her engagement photo is one of the most sought-after dresses she's worn.
For Kate and William's official engagement photos, she chose a white Reiss dress.
The couple looked lovely and happy as can be!
The couple attended a Christmas "Spectacular," Kate dressed in contrasting black and white with a bold necklace.
Kate wore all shades of neutral to launch a new RNLI lifeboat in the chilly February weather.
Kate and William visit their Alma Mater, St. Andrews University, for its 600th anniversary celebrations.
Kate wore a flared neutral trench coat while visiting Northern Ireland.
The dashing couple matched in navy blue suits while visiting an athletic track in Darwen, England.
Here comes the almost-bride... Kate smiled for the camera as she arrived at the Goring Hotel with her mom and sister the day before her wedding. She looked stunning in a patterned Issa dress and L.K. Bennett wedges.
The blushing bride steps out of Westminster Abbey, stunning in her Sarah Burton for Alexander McQueen gown.
The new Duke and Duchess of Cambridge kiss on the balcony of Buckingham Palace to cheers from the crowd.
Kate leaving Clarence House to attend the evening celebrations following her wedding to Prince William, in a pretty satin dress with an embellished belt showing off her tiny waist.
Kate and William headed out for their honeymoon the day after their wedding, Kate dressed in a simple belted blue dress and her L.K. Bennett wedges.
The Duchess met Michelle Obama in Buckingham Palace, wearing a cap-sleeved neutral Reiss dress.
Kate attended Derby Day, everyone dressed to the nines. The Duchess was in a white Reiss dress and beige fascinator.
Kate attended the 10th Annual ARK Gala Dinner in a stunning floor-length embellished Jenny Packham gown.
Kate and her sister Pippa attend a friend's wedding, both dressed in black and white patterned dresses and matching court shoes.
Kate and William were the picture of elegance at the 2011 Trooping the Colour ceremony for the Queen's birthday.
Kate wore her Jane Troughton cornflower blue brocade coat to the church service celebrating the 90th birthday of Prince Philip.
Kate and Camilla, Duchess of Cornwall, wearing pretty coats to the Order of the Garter Service.
Kate wore this bold Alexander McQueen military-style coat while visiting army Barracks in Windsor.
Kate wore a lace Erdem shift dress and nude L.K. Bennett heels while attending the wreath-laying ceremony at the National War Memorial in Canada.
Kate looks over her shoulder as she and Wills attend Canada Day celebrations in Ottowa. She was wearing a white Reiss dress with bold red accents in her fascinator and heels.
Kate was a bronzed beauty in this long-sleeved, purple Issa dress on the royal couple's Canada tour.
Kate wore this grey shift dress while in Canada, with a pointed collar and cuffed sleeves.
On day 4 of their Canada visit, Kate was seen in a brilliant blue Erdem dress with lace detailing on the bodice.
Kate wore this simple white shift during their Canada visit, carrying her favorite L.K. Bennett "Natalie" clutch.
The newyweds are cute and casual, in a rare embrace (public, at least!) after taking part in a dragon boat race.
Kate and Wills smile at one another, the Duchess dressed in Sarah Burton for Alexander McQueen on their 5th day in Canada.
Kate looked cool and casual in boat shoes and jeans.
The Duke and Duchess boarded a Canadian Airforce jet, Kate wearing J. Brand skinny jeans and L.K. Bennett slingback wedges.
Kate looked lovely in this canary yellow Jenny Packham dress, but battled with the wind at Calgary International Airport.
The Duke and Duchess arrived in Los Angeles, Kate in a bright green dress by one of our favorite designers, Diane von Furstenberg.
Kate wore this grey shift by London-based designer Roksanda Ilincic while in Los Angeles.
Kate and Wills attended the BAFTA Awards, Kate showing off a tiny waist in this Sarah Burton for Alexander McQueen floor length gown.
Kate in Santa Barbara, in a floral Jenny Packham dress.
Kate and Wills are back in the U.K., the Duchess wearing a beige v-neck dress for the opening of the state rooms in Buckingham Palace.
The Duke and Duchess visited Birmingham, Kate wearing Alexander McQueen.
Kate looked lovely in Amanda Wakeley as she and William visited the Royal Marsden Hospital.
A beautiful duo: Kate wore this crimson Beulah London gown, adding some vibrance to Fall in London.
Kate spoke with dinner guests at a reception at St. James Palace, wearing a silver one-shouldered gown.
Prince William, Kate and Prince Harry arrive at the Imperial War Museum, all dressed in their black-tie best.
Just before the holidays, the Duke and Duchess visited a homeless charity, Kate in a simple Ralph Lauren turtleneck dress.
The royal family attended a Christmas Day service, all in chic jackets and boots as they arrived at the church.
Attending the premiere of War Horse in the UK, Kate wore a lace Temperley London gown.
Kate visited the National Portrait Gallery in a belted grey jacket with a wide collar.
Kate wore this brown Hobbs coat to visit Liverpool, pairing it with black stockings and pumps.
Kate visited schools in Oxford, wearing a flared, bird-print Orla Kiely dress.
Kate wore this slightly distressed tweed Missoni coat to tea with the Queen and Camilla.
Kate wore this peplum skirt suit by L.K. Bennett and a James Lock hat during a visit to Leicester, England.
Kate wore an Orla Kiely dress for a visit in South London.
Kate looked cute and casual in coral skinny jeans while playing hockey with the Olympic team.
It was St. Patrick's Day, and Kate looked gorgeous in green, a belted Emilia Wickstead dress.
The Duchess is a hard worker! Helping to plant a tree, Kate still looked totally glam in a vibrant blue Reiss dress.
In one of our favorite looks, Kate had the embellishment on the neckline of this Matthew Williamson dress added just for her -- and she looked gorgeous.
Kate shows a little leg in this sleek Roland Mouret gown.
Attending an Olympic Concert, Kate dominated the red carpet in a lace-back Jenny Packham gown.
Ok, so maybe this photo is more about the puppy-love than the dress, but the Duchess still looks chic, even while playing with her and Wills' pup, Lupo!
Kate is pretty in pink at the Queen's Garden Party at Buckingham Palace, wearing an Emilia Wickstead dress and classic nude heels.
Kate wore a vibrant red Alexander McQueen dress, carrying a clutch by the same designer and sporting her favorite L.K. Bennett heels during the Diamond Jubilee celebrations.
The Diamond Jubliee continues, and Kate is seen in a nude lace Alexander McQueen dress with a Jane Taylor fascinator.
Kate waved from a carriage during the Trooping the Colour ceremony, wearing one of her favorite designers, Erdem.
Kate wore wellies to a polo match, with casual jeans and her pooch Lupo by her side.
Time for the Order of the Garter, and while most members of the royal family were in pale hues, Kate's Alexander McQueen stole the show.
Kate payed homage to Scotland with her clutch while she watched as Prince William was installed as a Knight of the Thistle in Edinburgh.
Kate looked chic in white at Wimbledon, carrying a fun animal print clutch.
Kate looked vibrant in Stella McCartney while visiting the National Portrait Gallery.
Our three favorite royals wait to receive the Olympic Torch at Buckingham Palace on it's route around Britain to the Olympic Stadium.
Kate and William visited Bacon's College with Prince Harry, Kate dressed in a grey and white checked dress.
Kate sparkled in this classic drape dress by Roksanda Ilincic.
The Olympics took London by storm, and the young royals weren't going to miss it. Kate sported UK colors in this striped top and navy jeans.
Wills and Kate celebrate a big win for the UK during the Olympics.
Kate attends the 10th day of the Olympics in a zipped-up windbreaker for the sailing events.
Kate looked chic and professional at the Paralympics Day 4 medal ceremony.
Kate and William kicked off the 2012 Diamond Jubilee tour in Singapore, the Duchess wearing a vibrant dress by Prabal Gurung.
On day 2, Kate wore this sheer Raoul dress and nude pumps.
She also wore a lovely Alexander McQueen skirt and jacket with Stuart Weitzman wedges.
Kate looked gorgeous in a floral Erdem dress during the British Gala reception.
On Day 4, Kate and William visited a Mosque, respectfully removing their shoes, Kate wore a headscarf and looked lovely in white.
While in Malaysia, Kate wore an ice blue lace Temperley London dress, with her hair pulled back in a pretty updo.
Kate wore a pale teal dress to visit the Memorial Cemetery in Singapore, looking back thoughtfully as she walked beside her husband.
Kate wore this sparkling Alexander McQueen to a dinner with Malaysia's Head of State.
The casual duo cross a bridge at a Rainforest Research center in Malaysia.
On day 6, Kate and Wills arrived at the Solomon Islands, Kate dressed in a bright Jonathan Saunders dress.
This yellow Jaeger shirtdress was light, bright and cool for the warm island weather.
The Duke and Duchess smiled in traditional Island clothing as they visited the Governor General's house.
The royal couple boarded a plane, Kate wearing a pale yellow eyelet dress and Stuart Weitzman wedges.
Kate prepared to dance with traditional dancers, in a much cooler grass skirt than we've ever seen.
Kate wore this navy eyelet Mulberry dress with traditional adornments during their visit, with her hair in natural waves.
Back in the UK, Kate and Wills attend the official launch of the new Football Centre, the Duchess wearing a Reiss coat.
Kate bends down to receive flowers from an adorable two-year-old, looking lovely in Alexander McQueen.
Kate attended a royal reception for team Great Britain's Olympic and Paralympic athletes, wearing a black floral dress with sheer sleeves.
Kate dons her lace Temperley London gown once more, this time adding a pop of red with her Alexander McQueen clutch.
Kate was glowing in an emerald green Mulberry dress for an opening at the Natural History Museum.
Kate wore this MaxMara Studio coat over a leopard-print dress for her and William's first visit to Cambridge.
Kate played hockey in Alexander McQueen while visiting St. Andrews University.
Kate left the hospital, after being admitted for severe morning sickness, in a navy coat by Diane von Furstenberg.
Kate looks on in a pretty Whistles dress after viewing her first official portrait.
Kate showed off her baby bump in a patterned MaxMara dress and simple pumps during a visit to Hope House.
Kate visited Grimsby in a gorgeous brown Hobbs coat, with her baby bump just starting to show.
Kate attended the fourth and final day of the Cheltenham Festival in a gorgeous peach wool coat by Joseph.
The Duchess of Cambridge attended the St Patrick's Day Parade at Mons Barracks in the same gorgeous green Emilia Wickstead coat of the previous year.
Kate Middleton wore this black Topshop dress as she visited the headquarters of Child Bereavement UK.
Dressed in a pretty white Redgrave Goat collarless coat over a dress from Topshop, Kate visited the headquarters of Child Bereavement UK.
Kate visits the Baker Street Underground Station in this teal Malene Birger coat, and true to royal style: a pretty black fascinator.
Kate visited the Great Tower Scout camp, keeping warm in green rain boots, a green army jacket and a knit crochet hat.
During a visit to Scotland, Kate and Wills met well wishers, played some ping pong, field hockey and basketball while she wore this tartan coat by British brand moloh.
Kate donned her red Armani coat, as seen on her in 2006, for the visit to Scotland.
Kate attended the National Review of the Queen's Scouts, wearing a mint green Mulberry Coat, Whiteley fascinator and her L.K. Bennett pumps. As you can see, the Duchess finally popped and her baby bump was fully visible.
Kate visited a primary school in a pretty Erdem floral dress.
Kate attended an event at the National Portrait Gallery, wearing a '50s-inspired, powder blue Emilia Wickstead dress and grey suede pumps.
Kate visited the Harry Potter sets at Warner Bros with William and Harry, wearing in a polka-dot dress by Topshop.
Kate visited Naomi House on the day of her wedding anniversary, wearing a peach coat by Tara Jarmon.
Kate was bold and bright at this year's Garden Party, wearing a bespoke version of the Marella coat by Emilia Wickstead.
Kate looked positively lovely at the Queen's Coronation service in one of her favorite designers, Jenny Packham, a light peach, almost nude lace empire-waisted dress.
Kate was glowing as she named a cruise ship in a printed Hobbs coat.
For her last official appearance before giving birth, the Duchess chose pale pink Alexander McQueen at the 2013 Trooping the Colour.
Kate wore a bespoke Jenny Packham blue polka dotted dress when she presented her son to the world, and she looked lovely.
Kate definitely had a new mom glow about her when she left the Lindo Wing of St. Mary's Hospital.
When Wills and Kate took off to go visit her parents in Bucklebury for the first few weeks after George's birth, she wore a dress by Seraphine perfect for new moms.
Kate and William pose with Prince George for the family's first official portraits at her family's home.
Kate wore another Seraphine knot-front dress for the photo while William was casual in a gingham button down. And in this photo, both the Middletons' family dog and Lupo made the cut!
Kate joined William out and about in Anglesey, wearing a Zara top, Paige denim jeans and a Ralph Lauren jacket.
Kate and William attended a gala for the Tusk Trust, Kate glittering in Jenny Packham.
Kate attended the SportsAid Athlete Workshop just a few months after having Prince George. She wore a pre-pregnancy outfit: her J.Brand skinny jeans, Ralph Lauren striped top, navy Smythe blazer and Stuart Weitzman wedges.
Kate chose Alexander McQueen for Prince George's Christening.
Kate attended a charity gala the following day, wearing an elegant navy Jenny Packham gown.
In honor of Poppy Day, William and Kate stepped out in London -- Kate wearing her long scarlet L.K. Bennett coat.
Kate wore a pretty black Temperley coat to honor Remembrance Day in London, wearing her hair in ringlets.
Kate recycled an Orla Kiely dress and her Aquatalia boots for a charity visit with William.
Kate looked lovely in London, wearing an Orla Kiely skirt and MaxMara coat as she received flowers from a young girl.
Kate attended the SportsBall, donning a laser-cut, black lace Temperley London cocktail dress, paired with her Jimmy Choo heels and Alexander McQueen clutch.
Duchess Kate attends Order of the Garter in a lovely pale blue Christopher Kane coat.
Kate is seen wearing Alexander McQueen to a military event in London.
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Today, the Duchess of Cambridge Kate Middleton visited the iconic Bletchley Park – the site of the UK's World War II codebreakers. The location is known as "Britain's best kept secret," famed for its work with the German Enigma and Lorenz cipher.
Bletchley Park was home to the Government Communications and Cypher School, a code name for Britain's peace-time codebreaking agency. The organization was founded in 1919, and by the 1940′s it was a critical aid to the war effort. Some say that Bletchley Park's decoding efforts shortened the war by 2 years.
For today's military-focused event, Catherine chose to repeat a look by McQueen. The military/nautical inspired shirt and blouse were first worn in 2011 to meet with victims of the Birmingham riots. Today, the outfit seems an appropriate nod to the occasion.
The navy pencil skirt is paired with a white blouse for a classic, vintage look. Catherine paired the ensemble with navy suede courts by Alexander McQueen and a Stuart Weitzman clutch. The Duchess of Cambridge accessorized the navy-and-white look with her sapphire drop earrings
The trip is notably close to Kate's heart – her father's mother, Valerie, worked as a civilian duty officer in the very huts she toured today. Michael Middleton's mother was a member of this heroic codebreaking team.
Bletchley Park recently underwent a year-long restoration, returning the area to its World War II glory. At the location, the Duchess of Cambridge toured the codebreaking huts. Catherine viewed the various interactive displays and demonstrations before meeting the Design and Management Team who worked on the restoration.
Clarence House even tweeted out a photo of Kate's paternal grandmother who looks just like Kate!
The Duchess also met with World War II codebreakers, including a woman who worked with Valerie, Kate's grandmother. These veterans were responsible for decrypting, translating and analyzing military encrypted messages sent to or from the enemy.
Click through the gallery above to see Kate's incredible style transformation!