Children wave from the top of a giant sand castle in Weymouth adorned with the Olympic rings and flags built to celebrate the fact there are 100 days to go until the 2012 London Games. London marked the beginning of the countdown on Wednesday. [Photo/Agencies]

As the clock reaches 100 days until the Games begin, Britain is putting the finishing touches on preparations that have been years in the making

Kew Gardens hosts the first in a series of celebrations on Wednesday to commemorate the 100-day countdown to the London Olympics. An oak tree was planted to mark Britain's role in the birth of the modern Olympic movement and giant Olympic rings made up of 25,000 flowers will be on display.

A city steeped in theater and pageantry is entertained by members of West End theatre shows assisted by British athletes taking part in a "West End Warm-Up" performance in Trafalgar Square.

Any initial trepidation about Britain's ability to stage a major global event has long vanished and last month the London organizing committee received a glowing endorsement from International Olympic Committee commission chairman Denis Oswald who proclaimed: "London is ready to welcome the world."

"We can feel that London is feeling the fever of the Games," Oswald said. "We are in no doubt that this summer will be a summer like no other in Britain."

Ensuring a unforgettable Olympics for London and the thousands of athletes and visitors who will pour into Britain for the Games opening on July 27 is the ultimate responsibility of organizing committee chairman Sebastian Coe.

A reminder of the disturbing ease with which big sporting events can be disrupted came this month when an intruder in the Thames disrupted the annual university boat race between Oxford and Cambridge.

The torch relay beginning in a month time, as protesters demonstrated during the 2008 Beijing Olympics relay, is similarly vulnerable, as are the street races such as the marathons and walks.

A banner is seen along with others made by scout and brownie groups to decorate an observation point opposite the Olympic Park in London last week. Westfield will be the main gateway to the Olympic Park in Stratford. [Photo/Agencies]

Need for balance

In an interview with Reuters to mark the 100-day landmark, Coe said there was a need to strike a balance between the safety of the competitors and ensuring spectators were not subjected to oppressive security measures.

"Competitors are doing something at the highest level, they have devoted over half their young lives to be there," he said.

"It is our responsibility to make sure they have a secure environment in which to compete but you do not want people coming to London feeling they have come to a siege town.

"We will get that balance right, we have to get that balance right. I am not being remotely cavalier or particularly sanguine about the nature of what we have to do, but we will get this right."

Asked about criticisms of the high cost of a sports event in grim economic times, Coe said there would be some validity to the argument if the Olympics was just a sporting festival.

"But of course it isn't," he said."We have regenerated in the process a large part of east London, we've transformed the lives of many young people living in east London.

"More broadly we have an opportunity to showcase this country in front of four billion people not just in sport but in our cultural communities.

"We have the ability to host 200 countries. There are millions of people the length and breadth of the country who are now helping us to deliver these Games.

"We have a torch relay that's going to go within 10 miles (16 km) of 95 percent of the population. So this goes way, way beyond just 16 days of sport."

Reuters in London