What would an Ancient Greek do before embarking on a new project? He would consult the oracle, a religious institution which made known the opinions of the gods. There were many oracles, but the most important was the one at Delphi. For more than a thousand years, Delphi was a sacred place dedicated to the god Apollo and home to the Oracle. The mystical connection with the god was used to make prophecies about the future. Nowadays, at just three hours drive from Athens, Delphi is one of the top tourist sites in Greece.

The Oracle

Central Greece is a land of steep mountains, with huge chasms between the mountains. Clinging to the cliff above one of these chasms is a relatively flat patch where a stream of water comes out of the cliff face. In ancient times, this was considered to be a sacred site, and a small temple may have been built to the Earth goddess. A quiet place in a remote uninhabited region with a dramatic view down the chasm to the sea; this was Delphi. But all that was to change: in the 8th Century BC, the people of Delphi started to worship Apollo, the beautiful sun-god. Pleased with his worshippers, Apollo granted them the ability to foretell the future, and the Oracle of Delphi was born.

Legend has it slightly differently: a giant monster called Python took up residence in Delphi and the god Apollo slew the monster. Zeus himself, the chief of the gods and father of Apollo, looked favourably on Delphi: he released two eagles from his home on Mount Olympos (in Northern Greece) and sent them to the ends of the earth. On their way back, they met at Delphi, and it was realised that Delphi is actually at the exact centre of the Earth. A giant stone called the Omphalos (Navel of the World) was placed to mark the spot¹.

The Oracle pronouncements were made by a priestess known as the Pythia. At first, she stood on the Sibylline Rock and declared the predictions of the Gods. Then a temple was built to Apollo, just up the slope from the rock, and the priestess made her predictions from there. The normal procedure was that a person would come seeking advice from the Oracle. After purification rites and, of course, suitable offerings to the priests, they would be allowed to pose their question. The priestess sat on a special Pythian Tripod. This had a circular top and three legs. She used to chew various leaves, working herself into a trance. Some reports say that she was aided in this by fumes which came out of the ground - more about this later. The priestess would eventually start to babble a string of incomprehensible sounds, under the influence of the god. Normal listeners could not understand what she was saying, but the priests would listen and would interpret. The official response of the Oracle would then be reported back to the person who had asked the question.

The Oracle of Delphi was sometimes amazingly accurate. The historian Herodotus tells us that King Croesus of Lydia decided to test all the oracles by sending out messengers to each of them. His particular question was to be asked of all the oracles at the same time of the same day, and it was this: 'What is King Croesus doing at the moment?' He would put his trust in the oracle that gave the best answer. Since he himself didn't know in advance what he would be doing, he reckoned this was a fair trial. When the day came, he decided to make a lamb and tortoise stew in a bronze pot with a bronze lid. Only the Oracle of Delphi correctly determined this in its answer:

And there hath come to my soul the smell of a strong-shelled tortoise
Boiling in cauldron of bronze, and the flesh of a lamb mingled with it;
Under it bronze is laid, it hath bronze as a clothing upon it.

It's a fair guess that some Greek guy somewhere is cooking a lamb stew at any given moment, but knowing about the tortoise was either a lucky fluke or divinely inspired!

The priests of the Oracle tended to be astute political advisers. They gave good advice, but if it was in any way debatable, they would couch it in such ambiguity that they could always claim that the god had meant something completely different if the message backfired. The same King Croesus went on to ask should he attack the Persian Empire. He was told that if he went to war, 'a mighty empire will fall'. He took this as encouragement, and attacked Persia. It was of course his own empire that fell.

The Rise of Delphi

At the start, the Oracle predictions were only made once a year, but as the success of the Oracle became famous, they started making predictions once a month. Even then there was a queue. Rich people were favoured, and their offerings made the sanctuary very well off. All sorts of small buildings were built around the sanctuary called 'treasuries' to hold all the offerings. Statues were erected to the gods. Distant Greek cities would compete against each other to make the most ostentatious offerings to the god. At the same time, physical competition was encouraged as well. The Pythian Games were held every four years at Delphi, in a specially built stadium at the top of the site. The winner would receive a laurel wreath (a crown of bay leaves).

To the east of the Sanctuary of Apollo, where all the business took place, was the Castalian Spring, the original site where the water comes cool and clean out the mountain. The priestess had to wash herself in this water, as did anybody wanting to ask a question of the gods.

Further to the east, a separate sanctuary sacred to the goddess Athena grew up, with temple buildings. There was also a gymnasium, where athletes would train for the Pythian Games.

The Sacred Wars

It wasn't all plain sailing for Delphi. Over the years, the locals attacked the shrine on at least three occasions, attempting to gain control of the shrine and loot the gold. These incursions were known as the Sacred Wars. Delphi managed to get help from other cities in repelling these invaders and successfully managed to stay independent.

The Decline and Fall of Delphi

By Roman times, Delphi was seen by many as a bit of a swizz, like the horoscopes in the daily newspapers today, but there was still a steady stream of supplicants with questions for the Oracle. Then in the 4th Century AD, the Roman Empire which ruled Greece was converted to Christianity. The Emperor Theodosius decided that the Oracle was a threat to Christianity, so he closed it down, along with all the other 'pagan' temples. Many of the treasures were taken² from Delphi to the capital of the Empire, Constantinople (now Istanbul).

The site of Delphi was abandoned and forgotten. Gradually, due to earthquakes and landslides from the steep mountain side, it was covered up, and in medieval times the small village of Kastro was built on the site.

In the 19th Century, archaeologists discovered the remains of Delphi under the village of Kastro. The entire village was moved further west and the archaeologists dug down to uncover the remains of the ancient site. It was soon opened up to the tourists, who now flock to the site in their millions.

The Sanctuary of Apollo

The main archaeological site in Delphi is the Sanctuary of Apollo. It lies to the east of the town. It is a steep site with a single main path known as the 'Sacred Way' which winds its way up from the gate to the temple and beyond. There are the ruins of at least 40 different buildings, the most important of which are:

• The Treasury of the Athenians - a small building that looks like a temple. This was the only one of the original treasuries that was intact enough to allow it to be reconstructed from the original materials.

• The Rock of Sibylla. This is the rock from which the Pythia originally made her prophecies, before she was moved further up the hill to the Temple of Apollo.

• The Stoa of the Athenians. This long narrow building has its back to the cliff, and the front is a colonnade.

• The Polygonal Wall. This wall supports the mountainside further up, and the terrace on which the Temple stands. Unusually, the large stones which form the wall are not rectangular, which would be normal for Greek buildings, but are all sorts of polygonal shapes. The whole wall is covered in writing: supplicants to the shrine engraved their prayers onto the wall. There's a great mix of styles in the writing, but unless you're an expert in Ancient Greek, it is unlikely you'll be able to read any of it.

• The Temple of Apollo. The temple itself must have been impressive in its day. Now all that remains is the base and a few of the columns.

• The Theatre - this small semicircular theatre was rebuilt in Roman times. Most of what you see now dates from that period.

Above the theatre, the path leaves the sanctuary and ascends steeply to the Stadium, where the Pythian Games were held. In Roman times, the wealthy Roman banker, Herodus Atticus, paid for stone seats to be fitted along one side, replacing the earth bank seating that was there before.

The Sanctuary of Athena

To the East of the Castalian Spring and below the road is the Sanctuary of Athena Pronaia. Athena was the patron goddess of Athens. The name Pronaia means 'in front of the temple'; the sanctuary was called that because visitors arriving by land from Athens would see the sanctuary standing in front of the Temple of Zeus.

The sanctuary has the remains of some temples, and probably Delphi's most celebrated building: the Tholos. This is a small round building which originally had columns all the way around it. Three of these and the architrave joining them have been reconstructed. This is one of the most photographed spots in Greece.

Also nearby is the Gymnasium, where athletes would train for the Pythian Games. There's not much of it left now.

The Museum

No trip to Delphi would be complete without a visit to the museum. Here the most important archaeological findings from the sites are displayed. Of particular note are:

• The Sphinx of Naxos, originally on a 10m column in front of the temple.
• A plate with a picture of Apollo, in virtually perfect condition.
• The Charioteer - an impressive bronze statue.
• The Omphalos - this stone marked the exact centre of the world, as seen by the Greeks. The original stone is gone, but this one is a copy made in Roman times.

Note the bizarre rules that apply to Greek Museums - you can take photographs of everything (as long as you don't use flash), but you are not allowed to take pictures of people with the artefacts.

Getting to Delphi

Any travel agent in Athens will be able to book you on a guided tour to Delphi and back. You can go under your own steam: it is a three-hour bus journey. If you decide to drive, take the E75 national route towards Lamia and Thessaloniki, turn off towards Thiva, Leivadhia, Arachova and Delphi.

The Modern Town of Delphi

The modern town of Delphi is about a mile from the archaeological site. It exists purely to cater for all the tourists who come to see the ruins. There are plenty of hotels, and plenty of fairly mediocre restaurants. There are also lots of bars.

Perched on the side of a steep mountain, space is at a premium, so it is very hard to find parking, if you've arrived by your own hired car. Even if your hotel claims to have parking, it probably doesn't. Take any space you can find, even if it is far from your hotel. You'll have to walk to the archaeological site, as there is nowhere there to park a car.

And Finally, The Fissure

Did the Pythia, the priestess of the Oracle, really inhale gases that came up out of the ground before making her predictions? Opinion is divided.

In Roman times, it was reported that she did. In the 1920s, scientists thought that the only source of such gases would be a volcano. They carefully examined the site of the Temple and concluded that there was no volcano nearby. There were no gases and never had been, they stated categorically.

Recently, in the early 2000s, an alternative view has come to light. Delphi is in a part of Greece which is highly active tectonically. That is, the rocky plates which cover the earth's surface move around and Delphi is on a join between two such plates (the Eurasian Continental Plate and the Aegean Plate). Fissures can open up and close again years later. Recently they've discovered the presence of gases in fissures directly below Delphi, although these gases have at the moment no way to the surface.

And the gas? Ethylene, the mildly hallucinogenic gas which induces feelings of euphoria and dream-like visions. Could it have been in this state that the Pythia received her message from the gods? No doubt, Apollo could have arranged this with his brother, Poseidon the Earth-Shaker, who was believed to be responsible for earthquakes. In this way, Apollo's believers were guaranteed a direct line to their god.