Get Involved: CYCLING - ROAD
London's most iconic landmarks will be on show as the road race events take the Olympic cyclists on a whistle-stop tour of the capital.
Hugh Porter, BBC Sport
"The beauty of the road race is that the sprint finish on The Mall and climb on Box Hill will give you memories you will never forget. All British hopes will be pinned on super-sprinter Mark Cavendish, who has won green jerseys at the Tour de France. The style of course should see a lot of the other sprinters put Cavendish under pressure, such as Australian Matt Goss. If Lizzie Armitstead gets the right support from her team, she could get on the podium. The Italian women will be a big threat to her. In the time trial, Bradley Wiggins will be a big home favourite, but the course could be too flat for Emma Pooley."
With Buckingham Palace in the background, riders such as home favourite Mark Cavendish will set off from The Mall on a gruelling journey that takes them through Westminster and across the River Thames.
While the medals are handed out on an individual basis in the road race, Cavendish will require help from his four other team-mates as tactics can play just as important a role as individual stamina.
In contrast, competitors ride alone in a battle against the clock as they sprint across the course at Hampton Court Palace at breakneck speed in the time trial.
With many heading to the Olympics fresh from their exertions in the Tour de France, London 2012 should provide the platform for several of the sport's greatest rivalries to be resumed.
Why is it good for you?
Road racing is an exciting and physically demanding sport, which burns approximately 844 calories per hour. The strain of keeping the bike in motion over long distances increases the heart rate, lowers blood pressure and improves endurance.
As the thigh, calf and hip muscles are in constant use, it is an effective way to help build lower-body strength.
Unlike other high-energy sports, bike riding has a much lower risk of injury as there is none of the physical contact between athletes found in football or rugby, while it is much gentler on the knee and ankle joints than long-distance running.
Biking does not only have to be done as a sport. A study by the International Bicycle Fund found commuters who begin to ride their bicycles to and from work instead of driving lose an average of 13 pounds during their first year of biking.
As road racing is a team-based pursuit, it is an excellent way to develop communication skills and learn to work effectively with other people.
Clubs also offer a variety of social events beyond just riding.
Approximately two million people in Britain cycle at least once a week, and there are more than 80,000 members of cycling clubs. The ability to ride comfortably and safely in a bunch of riders is perhaps the essential skill of road racing.
It has a strong club-based culture, so a great place to start is by joining a club which regularly runs training rides on public roads.
Before taking to the course, it is essential to wear safety equipment such as a helmet, cycling gloves and elbow and knee pads. If you are riding on public roads, it is important to wear high visibility gear.
Can you compete?
Get your performance under pressure analysed in just 20 minutes by four-time Olympic gold medallist Michael Johnson
Some clubs allow members to hire bikes and helmets. A decent starter bike costs around £100-£300, and it is important to buy a road bike as mountain and hybrid BMX bikes are ill-suited to ride on for long distances.
Training days and taster schemes are run for people of all ages and abilities throughout the year. Visit the British Cycling, Cycling Ireland, Scottish Cycling and Welsh Cycling websites for more information.
Small fees are often required to take part in the 3,000+ meets held annually throughout the country.
For parents looking to get their children started in competitive racing, British Cycling are running a number of events for under-16s throughout the United Kingdom this year. Visit the 'Go-Ride Racing' website for more details.
Sky Ride are offering free cycling events across the country throughout the summer. Their website also contains information about where you can find your nearest cycling route.
Fun, free and informal bike rides just for women are also available through Sky Ride's Breeze scheme.
Want to get involved with sport in your local community? Why not Join In ?
'Join In Local Sport' aims to get as many people as possible to turn up and take part in activities at their local sports facilities on 18/19 August, 2012 - the first weekend between the Olympic and Paralympic Games.
The aim of the initiative is for every sports club and community group in the UK to put on a special event in a bid to encourage more people to get involved as members, supporters or volunteers.
More than 4,000 local sports clubs will be opening their doors to host events and show people just how they can get involved.
As well as tips on playing sport there will be information on coaching, supporting and how to help out.
Find an event near you.
The competition format at London 2012
- There are two medal events in both men's and women's road cycling - the road race and the time trial.
- The road race course, which includes a 15.9km circuit of Box Hill in Surrey, begins and ends in The Mall. On Saturday 28 July, 145 riders will take part in the men's event, with 67 riders featuring in the women's event on Sunday 29 July.
- The time trial course begins and ends at Hampton Court Palace. Both races take place on Wednesday 1 August, with 40 riders competing in the men's event and 25 riders in the women's event.
The rules at London 2012
The men's and women's road races see all competitors start together, the first across the finish line winning gold, while in the men's and women's time trials, riders start 90 seconds apart and the winner is the rider with the fastest time over the course.
Both events are held over a single lap, with slight variations in the men's and women's courses due to the different distances.
Great Olympic moment
The Atlanta Games in 1996 saw Miguel Indurain claim the final victory of his legendary professional career. Two weeks before, the Spaniard had flopped in his attempt to win a then unheard of sixth consecutive Tour de France title. Indurain's remarkable inner strength saw him fight back and claim the debut Olympic time trial gold.
The men's event is over 250km (156 miles), with the women's event over 140km (87 miles). The men's time trial will be held over a 44km circuit, while the women's time trial will be held over a 29km course.
Cyclists can take part in both events, but only riders entered in the road race can take part in the time trial.
In the road race, the competitors will head south-west through London from the start point at The Mall. They cross the River Thames at Putney Bridge and go past Hampton Court Palace before they reach the Surrey section at Box Hill.
The men will compete nine loops of Box Hill, and the women two loops, before the riders head north through Leatherhead, Esher, Kingston-upon-Thames, Richmond Park and back to The Mall for the finish.
In both disciplines, bike changes or repairs are permitted, but only by team technicians from the team car, or by a neutral assistance service, and if a rider's bike is damaged, he/she can finish the race and be ranked if he/she crosses the finish line with the bike.
In the road race, a tie will be called if the race cannot be decided by a photo-finish. In the time trial, times are measured to 1/1000th of a second and if two or more riders have the same time, it will be called a tie.
Ones to watch
World champion Mark Cavendish is aiming to become the first British man to win Olympic road race gold.
Triple Olympic track gold medallist Bradley Wiggins has his sights set on the time trial.
Versatile Dutch rider Marianne Vos is already an Olympic track champion and a world cyclo-cross champion - can she add Olympic road race gold to her already impressive CV?
The sport of bicycle racing has been around since the early 1800s when the precursors to modern bikes, the 'velocipedes' were invented.
Did you know?
The 1920 Olympic road race course in Antwerp was intersected by six railway crossings. Harry Stenqvist of Sweden was held up for four minutes at one of them as a train went past - luckily for him, organisers had posted time-keepers at each crossing to record any delays, and the subtraction of the four minutes from his finishing time earned him a gold medal.
Before the end of that century in France, long-distance races from city to city such as the 572km (355 mile) race from Bordeaux to Paris, or the punishing 1280 km (795 mile) race from Paris to Brest and back to Paris, were contested.
Road racing's most popular and enduring event, the Tour de France, was then established in 1903.
A number of road-race disciplines were present at the inaugural Modern Olympics in 1896, including an 87km contest that started and finished in Athens, as well as a 12-hour timed-event.
There was no road racing at the next three Games, before it returned to the schedule in 1912 and has remained a permanent part of the Olympic programme ever since.
The 1984 road race in Los Angeles marked the first time women had competed at a cycling event at an Olympics.
Road racing has gone on to become the highest-profile cycling discipline thanks to the Tour de France, which attracts global viewing figures of around 44 million each year.