A military walk-through of the wedding route took place for Prince William and Kate Middleton's wedding on Friday.
Members of the armed forces in full ceremonial uniform took part in the parade at Wellington Barracks in Westminster.
Carriages also took part in the procession to Westminster Abbey.
A music rehearsal at the Abbey was set to follow.
The Abbey closed its doors to the public on Tuesday so that preparations could get under way, but reopened after the walk-through [Watch video].
Avoiding catastrophe at the royal wedding
Security is the key issue for the royal wedding, and at a press briefing on Tuesday, officials urged the public to help with their efforts. "We really need you to be our eyes and our ears," said Metropolitan Police Assistant Commissioner Lynne Owens. "If you see anybody in the crowd that is acting suspiciously, please bring it to the earliest attention of our officers."
Officials have been planning the security for the wedding for 22 weeks. Sixteen known troublemakers have already been banned from London on the big day.
According to Metropolitan Police Cmdr. Christine Jones, there is no intelligence indicating a threat to the wedding, but authorities are still taking precautions to avoid any catastrophes.
Britain is no stranger to terrorism. On July 7, 2005, four bombs went off in Trafalgar Square during the morning rush hour - three in the subway and one in a bus. The bombing left 56 people dead and 700 injured, and it brought the city to a halt. Islamic fundamentalists had taken responsibility for the bombing.
And almost one month ago, 500,000 people gathered in Trafalgar Square to protest economic cuts. Dozens of civilians and officers were injured, and there were 200 arrests.
Officials are worried that the group that protested will show up at the wedding. They asked for a permit to be at the Abbey, but the permit was denied. There are reports that the protesters might still show up spread out throughout the crowd [Watch video].
Onlookers camp out ahead of wedding
Some 5,000 police officers will line the streets trying to control hundreds of thousands of onlookers - not just showing up the morning of the wedding, but literally camping out, some of them for days.
Guen Murray, 76, traveled from Norfolk, England and set up shop on the sidewalk across the street from the abbey.
"I'm very keen on the royal family, and it's always a happy day," she said. "I just want to be part of it."
She plans to camp out there until Friday to secure her location for the wedding [Watch video].
Journalists invade Kate Middleton's hometown
Villagers in the quaint town of Bucklebury where Kate Middleton grew up have had to make adjustments to deal with the invasion of journalists.
A convenience store owner, who has been invited to the wedding, was seen trying to work while camera crews surrounded him, including Carson Kressley, who is on assignment for Oprah Winfrey. Kressley has stormed the village with his hilarious high-energy personality.
Simon Kelly, who owns the Bladebone Inn in Bucklebury, didn't get an invite, but he knows the Middletons, and that's good enough for the media.
"I don't mind it actually. It makes my day a little bit lighter," he said. "Sometimes it can get a bit annoying, but it's fine if it's in a good cause."
The Old Boot Inn has become quite popular these days, thanks to owner John Haley getting an invite to the wedding. With his outgoing personality, he is a gold mine for journalists around the world.
"It's crazy, it's going to be a really busy week," he said with a laugh [Watch video].
Chef explains tradition of afternoon tea
The British are all about tradition, and one tradition that has been offered at London hotels for nearly 200 years is afternoon tea. At London's royal five-star hotel Royal Horseguards, the pastry chef created some goodies in honor of the royal wedding to go with tea.
Afternoon tea started in the 1800s as a way to get through the gap between lunch and dinner. Head pastry chef Joanne Todd said a duchess invited friends over for tea, sweets and sandwiches, and it caught on.
According to Todd, afternoon tea is based around light pastries, finger sandwiches and scones.
"This is something to take as a light snack in the the afternoons," she said.
Afternoon tea is for all ages, but to keep with British tradition, don't extend your pinky when drinking tea [Watch video].
ABC7 anchors David Ono and Michelle Tuzee are in London for the royal wedding. Look for their live reports all week leading up to Friday's ceremony on Eyewitness News.
"Good Morning America" will have special royal wedding coverage Friday beginning at 1 a.m. PT.
Prince William and his best man Prince Harry will arrive at Westminster Abbey at 2:15 a.m. PT.
Queen Elizabeth II will arrive at the abbey at 2:45 a.m. PT.
Kate Middleton will head to the abbey from her hotel at 2:51 a.m. PT.
The actual wedding ceremony is set to take place 3 a.m. PT.
For the full wedding day timeline, click here.