Prince William and Princess Catherine leave Westminster Abbey in a carriage following their wedding ceremony in London on April 29, 2011. The former Kate Middleton married Prince William in front of 1,900 guests. The couple will now go by the Duke and Duchess of Cambridge. UPI/Kevin Dietsch | License Photo
LONDON, April 29 (UPI) -- Prince William and Catherine, duchess of Cambridge, left Buckingham Palace after a reception Friday with the prince behind the wheel of his dad's Aston Martin.
An estimated 2 billion people watched William and college sweetheart Kate Middleton exchange wedding rings and vows in a regal ceremony at Westminster Abbey.
The couple, who received the titles the duke and duchess of Cambridge from Queen Elizabeth II, left the reception at Buckingham Palace for Clarence House. Another reception was scheduled for the evening.
The convertible -- top down because skies were sunny -- was festooned with red, white and blue ribbons and bows, and heart and star Mylar balloons attached to the rear bumper.
The license plate read: "JU5T WED."
Prince Charles has owned the Aston Martin DB6 since 1969. In June 2008, at Charles' request, the car was converted to run on E-85 bioethanol made from English wine wastage.
Accompanying William and Kate was a search-and-rescue helicopter in a special fly past, the royal wedding Web site said. William is a search-and-rescue pilot based in Anglesey, Wales.
The aircraft was flown by members of B Flight 22 Squadron, the squadron to which William, second in line to the British throne, is attached.
After the public wedding festivities ended, hangers-on at parks and in the streets of London danced to piped-in music to celebrate the wedding of the popular couple. Impromptu conga lines formed. CNN reported there were more than 5,000 street party applications in London alone.
Guests inside Westminster Abbey wore morning coats, high-fashion frocks and designer millinery while the attire of observers in Hyde Park and elsewhere under the skies ranged from cocktail dresses to dresses sown from British flags to shorts and T-shirts. And hats.
The royal wedding meant a four-day weekend of celebration.
With the world watching, William kissed his bride twice before a cheering crowd at Buckingham Palace.
"You look beautiful," William told Kate when she stepped beside him at the abbey's altar.
Less than an hour later, Kate told William, "I'm so happy" as they sat in an open carriage ferrying them from the abbey to the palace.
Tens of thousands of people walked in an orderly fashion to the palace, hoping to catch a glimpse of William and Kate's kiss on the balcony under sunny skies. Among the military units marching to the palace were British troops who served in Afghanistan.
After giving Kate a sedate kiss on the lips, William yielded to chants of "kiss again" to an appreciative crowd.
While the ceremony was subdued inside the abbey, shouts erupted among the hundreds of thousands of people watching throughout London when the two were pronounced man and wife.
"Those whom God has joined together, let no man put asunder," said Rowan Douglas Williams, the archbishop of Canterbury, who presided over the exchange of vows and rings.
"For as much as William and Catherine consent together in holy wedlock … I pronounce that they are man and wife in the name of the Father, the Son and the Holy Ghost."
As they left the sanctuary, the newlyweds paid respects to Queen Elizabeth II. Several church ministers politely clapped as the royal couple passed.
Church bells, orchestral music and a roar of cheers greeted the new duke and duchess of Cambridge as they emerged from Westminster Abbey after the wedding.
Kate was escorted by her father, Michael Middleton, to the sanctuary where William and best man Prince Harry waited.
Her sister, Pippa, carried the bride's train, surrounded by flower girls and ring bearers.
The congregation sang the hymn, "Guide Me, O Thou Great Redeemer," which was sung at the funeral of William's mother, Princess Diana.
After the exchanging of vows and rings, the newly married couple participated in a hymn, listened to a scripture reading by Kate's brother, James, and to a hymn commissioned by the Rev. Dr. John Hall as a wedding present. When William, Kate and their witnesses disappeared behind the sanctuary to sign the marriage register, the wedding guests were treated to a musical interlude.
A fanfare of horns, church bells, cheers and shouts of good cheer ushered the vehicles as they snaked through the streets to the cathedral, a prelude to the revelation of the well-guarded secret of Middleton's wedding dress.
When she entered the vehicle to go to the abbey, well-wishers caught a fleeting glimpse of Kate's gown designed in collaboration with Sarah Burton of British designer Andrew McQueen's fashion house. The stylish gown featured Chantilly lace sleeves and bodice with the V-neck neckline she favors, a tiara (something old borrowed from the queen) and a blusher veil over her face. The stylish form-fitting bodice flowed into a full skirt and train. Simple teardrop diamond earrings (something new given to her by her parents) graced her earlobes. She wore no necklace.
William wore the distinctive uniform of colonel of the Irish Guards. Harry wore the uniform of captain of the Royal Horse Guards and 1st Dragoons, a British army cavalry regiment that's part of the Household Cavalry.