By Mark Barden

As preparations for the London 2012 Olympics gather pace, 27 April marks the centenary of the start of the first Games to be held in the British capital.

BBC Sport looks back at the 1908 Olympiad, its highlights and heroes, as well as its quirks and controversies.

The 1908 Games were due to be held in Rome, but the eruption of Mount Vesuvius in 1906 left Italy needing to divert resources into disaster relief and rebuilding.

With time running out, the International Olympic Committee (IOC) asked Britain to step in as host. That gave London less than two years to prepare.

But with Lord Desborough, the British Olympic Association's dynamic chairman, to the fore, and the support of King Edward VII, the challenge was accepted.

The Olympic Stadium was ready in good time for the Games

A Franco-Britannic Exhibition was to be held in west London in 1908, and the canny Desborough did the kind of deal which would leave London 2012 boss Lord Coe still in his blocks.

In return for a share of gate receipts, the exhibition organisers agreed to fund and build a 66,000-capacity stadium next to their site, and even donated £2,000 towards its running costs.

So hats off, gentlemen, to Lord Desborough, the first hero of the 1908 London Games.

DID YOU KNOW? The White City area of west London takes its name from the marble cladding used on the exhibition pavilions.

Politics reared its head at the 1908 Games when the US team declined to dip the Stars and Stripes when passing the King at the opening ceremony.

As competition began, the Americans were soon lodging allegations of biased judging and bemoaning the fact that events were staged using British rules.

Halswelle's win is still the only walkover gold in Olympic history

The latter led to the IOC ensuring in subsequent Olympics that standard international rules were applied to avoid similar disputes.

One of the biggest came when American John Carpenter won a four-man 400m final but was disqualified for impeding Britain's Wyndham Halswelle.

A re-run was ordered but the three Americans refused to take part, so Halswelle ran unopposed to take gold.

As a result, the 400m at the 1912 Games in Antwerp was run in lanes. The International Amateur Athletics Federation was founded in the same year, in part to harmonise the variety of rules that had developed around the world.

DID YOU KNOW? Capt Wyndham Halswelle was killed by a sniper at the Battle of Nueve Chapelle during the First World War.

This year's Summer Games in Beijing will be done and dusted in a little over two weeks, but the 1908 Olympics were the longest ever, running from the end of April until late October.

That allowed plenty of time for some idiosyncratic inclusions in the programme of events, including - for the first and only time - tug of war.

The competition was dominated by the long arm of the law, with British police teams taking gold, silver and bronze.

The Liverpool St Police tug-of-war team take the strain in 1908

Powerboating was another sport which made its sole Olympic appearance in 1908, with three races held in choppy conditions in Solent. Britain took two golds, and France the other.

Conditions were decidedly chilly at the Prince's Skating Club in Knightsbridge, where Olympic ice skating took place in April.

In the days before separate Winter Olympics were staged, Britain won six medals, although two of the four events only had three entrants.

Britain also enjoyed swimming success, but won no plaudits as the water in the 100m open-air pool in the middle of the Olympic Stadium turned distinctly swampy as the Games progressed.

606: DEBATE Do you have any links to the 1908 Games?

Organisers weren't helped by heavy rain during the summer which turned the infield of the stadium into a mudbath.

By the end of the swimming events, the water was so murky that competitors were colliding with each other.

DID YOU KNOW? Diving and field hockey made their Olympic debuts in 1908.

You may not know who won the marathon at the 1908 Games, but the name of the first man to cross the line only to be disqualified is part of Olympic lore.

Italy's Dorando Pietri (see main photo, top) was in a state of near-collapse as he entered the Olympic Stadium and tottered towards the tape.

He actually had to be helped to his feet more than once, and was assisted at the finish by two race officials.

Italy's Dorando Pietri thought he had won the 1908 Olympic marathon but was disqualified for receiving help from race officials

Because of that he was stripped of victory, and the gold medal went instead to America's JJ Hayes - so it didn't all go against the USA in London.

Perhaps Pietri was nobbled by the extension of the marathon course by 385 yards so the start could be seen by the Royal Family at Windsor Castle.

Eyewitness accounts of the race have also suggested he may have had the odd swig of brandy proffered by spectators along the route.

Whatever the truth of the matter, his plight touched the heart of the public, and he was presented with a special trophy by Queen Alexandra.

To this day, all marathons are still run over 26 miles and 385 yards, thanks to royal intervention in 1908.

DID YOU KNOW? Pietri's exploits are commemorated in White City by a road named Dorando Close.

"Legacy" is a buzzword used by organisers of the 2012 London Olympics - the lasting impact they hope their Games will have.

The 'roll of honour' plaque at the BBC's Media Village in White City

But what of the London's first Olympics - what endured after they finally came to an end on 31 October?

The judging controversies at the 1908 Games led to the standardisation of track and field rules at future Olympics and other major events.

They also led to the IOC appointing officials from an international pool rather than leaving it up to the host nation.

An opening ceremony in which national teams paraded behind their flag also became standard after the London Games.

The event also set the bar for future British teams, with the hosts topping the medal table for the only time, winning 56 golds, 51 silvers and 39 bronzes.

Finally, the 1908 Games bequeathed a stadium to London that was used for a variety of sports until its demolition to make way for new BBC premises in 1985.

The finishing line of the old track is marked outside the BBC's White City building, and in 2005 a special plaque was unveiled by IOC president Jacques Rogge to commemorate the 1908 Olympics.

Will the 2012 stadium gradually taking shape in East London still be in use 77 years after the Games are over?