Today's Olympic Games may seem a thoroughly modern affair. But how did the original event compare with today's spectacle, asks Greek historian Prof Paul Cartledge.

What they wore - or didn't

Survival of the fittest Which ancient Olympic Games have stood the test of time? "Of the ancient running events only the 'stade' (200m sprint), double stade (400m), and 'long' race (c. 5000m) have survived," says Prof Cartledge. "Besides those, there were the combat events. Of these, wrestling and boxing survive (but in different forms). Wrestling was also one of the five events of the ancient pentathlon. "The other four were the stade (200m), javelin-throwing, discus-throwing and standing long jump. The ancient equestrian, chariot and mule-racing events have no modern Olympic parallels."

The Olympics were strictly for men, as far as the athletics and combat sports were concerned.

Women weren't even allowed to watch. However, women might compete in the equestrian events, but only by proxy as owners of the horses and chariots. The first woman victor on record was a Spartan princess.

One reason for their exclusion, perhaps, was that the athletes, boxers and wrestlers all competed in the nude.

The ancient Greek word for "to exercise" meant literally "to be stark naked". Our gymnastics words are derived from this cultural peculiarity of theirs, for which the explanation was probably ultimately religious.

The Games were a religious festival in honour of Zeus and demanded out of the ordinary devotions.

Jockeys and charioteers did wear some clothes but they were hired hands, not the owners of the chariots or horses, who alone were credited with the victory and claimed the honorific prize.

Which events were contested?

Media playback is unsupported on your device Media caption Matthew Stadlen and Prof Paul Cartledge visit an ancient Olympic running track

The single original event was the "stadion" or "stade", which was a roughly 200m sprint. The 4th Century BC track that is still visible and visitable at ancient Olympia measures just over 192m.

To the stade sprint were added successively: a 400m sprint, a roughly 5,000m "long" race (24 laps), long jump, discus-throwing, javelin-throwing, wrestling, boxing, extreme wrestling-cum-judo, and a race in armour (the one exception to the rule that athletes competed naked - though their only body-coverings were a helmet and shin-guards), and equestrian events - four-horse chariot race, horse races, and mule-cart race.

The purpose of the Games

The Olympics were explicitly a religious festival dedicated to the worship of the most powerful of all the many Greek divinities, Zeus of Mount Olympus (the highest mountain in Greece, almost 10,000ft).

Image caption Viewpoint from the temple of Olympian Zeus in Athens

Other divinities were worshipped in the area of the sanctuary at Olympia, for instance Zeus's sister-wife Hera (with a fine temple), and the hero Pelops who was credited as one of the Games's founders (with an ash-altar); but Zeus received the lion's share of the pious adulation, including a massive temple containing a gold-and-ivory cult-statue by the leading artist of the day, Pheidias of Athens, that was later ranked as one of the seven wonders of the ancient world.

Where did the Games take place?

The Games were always held at the same site, in a rather remote location in the north-west Peloponnese that was quite hard to get to (usually on foot) even from the main political centres of Athens and Sparta.

Find out more On The Road With The Ancient Olympians can be seen on the BBC News Channel on Saturday 30 June at 15:30 and 21:30 BST and on Sunday 1 July at 22:30 On The Road With The Ancient Olympians

Competitors and spectators were drawn not just from mainland Greece but from all over the entire Greek world, which stretched from Spain to Georgia, far beyond the Aegean basin.

After the conquests of Alexander the Great, who died in 323BC, Greeks were to be found permanently settled as far as afield as Afghanistan and Sind. The site was known as Olympia after Zeus's cult-title "Olympian", which was derived from Mount Olympus, a mountain many miles to the north of the Olympic site.

How athletes and other victors were rewarded

Winning was its own reward, in theory. A symbolic olive-wreath crown culled from trees growing in Olympia's sacred grove, the Altis, was the sole prize on offer. This was for the winner only - there were no silver or bronze medals.

Image caption Victors may have been immortalised in sculptures

But a victor's home city might also bestow on him a substantial one-off monetary reward or a lifetime's free dining in the town hall. And the victor might himself commission a leading poet such as Pindar to immortalise his fame in an ode to his joy or commission a sculptor to fashion a lifesize representation of himself or herself in bronze or marble to be dedicated to a god either at Olympia or in his or her home city.

At the end of the 5th Century BC the city of Acragas in Sicily (modern Agrigento) honoured a favourite son, Exaenetus, a two-times victor in the stade race, with an escort of 300 chariots drawn by white horses and tore down a portion of the city walls to enable him to re-enter in triumphant majesty.

A century earlier, the wrestler Milo from Croton in south Italy was the Usain Bolt of his day. Not only did he win six times at Olympia and at many other Games, but he also performed legendary feats of bull-carrying and beef consumption.

An international event

At first and for many centuries the Games were all-Greek and only-Greek, which is what "panhellenic" means. Put negatively, barbarians (non-Greeks) need not apply.

But when Rome conquered Greece, in the second Century BC, Romans objected to being called barbarians and demanded honorary Greek status to enable them to compete. Which they did, for the most part, with great success.

The Games indeed continued under the Roman dispensation every four years without a single break until 393AD, when they were terminated by a devoutly Christian Roman emperor, Theodosius I, on the grounds that they were polytheistic and pagan.

Getting it all wrong

Another Roman emperor who notoriously did not quite appreciate the ancient Olympic spirit was the supposedly philhellenic Nero, who died in 68AD. He demanded, with bribery and menaces, that the panhellenic Greek committee postpone the due date of the Olympics for two years so that he could fit in his appearance at the Games with a Greek imperial tour in 67AD.

He was thrown from his 16-horse chariot but nevertheless was awarded the victor's olive wreath crown. Such was imperial power in those days - not all that different from Hitler's Berlin 1936 Games, perhaps.

Let us hope that the quintessentially Greek spirit of competitiveness (it's from their word agonia that our word agony comes) takes a pleasantly different form in London 2012.