This is where the Sahara and the Mediterranean touch and embrace. It is in Libya where the beauty of the Hellenic world meets the modern reality of Colonel Gaddafi

Three lines of dragon's teeth had been pulled across the desert road, guarded by a squad of jeeps and their rear-mounted machine-guns. As we slowed to a halt, the guns swivelled around to face us.

Three lines of dragon's teeth had been pulled across the desert road, guarded by a squad of jeeps and their rear-mounted machine-guns. As we slowed to a halt, the guns swivelled around to face us.

The soldier in command was very young. With his shirt open to the navel and his camouflage turban flapping in the wind, he could have stepped straight from a fashion shoot. I smiled and murmured a polite Arabic greeting, but my normally cheerful Libyan guide and driver went very quiet. No one could understand the point of this new checkpoint. Only months later did I find out there had just been a failed attempt to assassinate Colonel Gaddafi in the Cyrenaican hills.

Such was my introduction to Cyrenaica, a place which has always been touched with the allure of an historical mystery. Maps of North Africa are dominated by the swirls of yellow and ochre that represent the Sahara. This is especially true of eastern Libya where the Sirtic and Libyan deserts reach right up to the Mediterranean shore.

The idea that right in the centre of this famously arid zone you could walk through green mountains and ruined Greek cities seemed most unlikely. I had got used to finding evidence of the Phoenicians, Romans, Moors and Turks all over North Africa. But Greeks: surely they belonged elsewhere, in Sicily, southern Italy, the Black Sea and the Aegean shore. There were exceptions, of course, like Agathocles assaulting Carthage and Alexander the Great riding to the oasis of Siwa to seek enlightenment, but the idea of Greeks permanently settled in North Africa seemed incongruous.

Later that day we drove east to the site of Cyrene. In the evening light I stumbled into the Forum of Proculus. The mute yellow stones glowing in the dusk had the force of an aesthetic thunderbolt. I stood surrounded by over a hundred doric columns, within a high perimeter wall. At the centre was the remains of a temple, while to one side it was possible to make out the shape of a basilica. It was all I had time to see that day, but it was enough. I had become addicted to the place.

Over the following days, Cyrene revealed herself to be one of the greatest and most beautiful cities not only in North Africa but also in the entire Hellenic world. Her situation, perched on a limestone escarpment with a distant mountain-guarded view of the sea, is rarely equalled but never surpassed. The temple-encrusted sanctuary of Apollo at Cyrene can be compared only to that at Delphi, though here there are no crowds to break the sanctity and the nymph's spring still supplies a trickle of cool water. The miraculous is still tangible here, as was witnessed when a torrential shower washed away the soil to reveal the famous statue of Aphrodite of Cyrene to an incredulous Italian army encampment. It is said that the passion to locate the missing parts of her body drove forward the first frenzied years of excavation.

It was a glimpse of more massed columns that attracted me to Cyrene's temple of Zeus. Now surrounded by grazing cattle, it once dominated the poorer suburbs of the city. Larger than that at Olympia and than the Parthenon of Athens, it has the additional distinction of being destroyed by a Jewish revolt. Perhaps some kinsmen of that shadowy gospel figure, Simon of Cyrene, helped topple the statue of Zeus and gouge out his jewelled eyes.

I walked through the cattle to find the circus track, now a pastoral, silent declivity. Cyrene was the Newmarket of the old world, the acknowledged breeder of champion horses and charioteers.

I had first heard of Cyrene's Agora through the poets. Pindar describes the centre of the city as: "A straight hewn way, level and paved, sounding with the tramp of horses. And there at the far end of the market place He lies apart in death."

The "he" of this verse is the King Battus, the founding father of the city whose tomb was a well known feature of the ancient city. Catullus, writing from Rome several centuries later, makes another reference to Cyrene's royal tomb, though it is wrapped up in his demands for endless kisses from his indifferent mistress. The mausoleum has since been lost, found and then found elsewhere by rival archaeologists.

One loses count of how many theatres the city boasted at any one time. Not so the vast domain of Jason Magnus, complete with marble floors, mosaics and statues of the nine graces. Another much smaller villa is associated with Synesius, Cyrene's premier man of letters.

Synesius studied at the great academies of philosophy at Athens and Alexandria, but he never lost his love for his homeland. He served as ambassador for Cyrene to the Imperial Court at Constantinople and was later persuaded to become a local bishop. He only accepted the post providing he was allowed to keep his wife, his strong doubts on the after-life and his passion for hunting ostriches. At the end of his life, his ancestral estates were destroyed by raiding parties of Saharan tribes, just as in faraway Britain the barbarians began their depredations. The province of Cyrenaica rapidly shrunk back to the coastal strip.

Following history we took the coast road down to the port city of Appollonia. I walked through sea-scented forests of grey marble columns, which mark out the city's four great Byzantine churches. Above them stood the warren-like palace of the governing Dux.

There is nothing the least bit ephemeral about these Byzantine buildings. In the countryside east of Appollonia, it is possible to walk through coastal scrub and stumble across three monumental churches around the village of Ras el Hilal. Even deep inland, at Ksar Libyia, the churches are furnished with magnificent mosaic floors paid for by the local bishop. There are images of the famous lighthouse of Pharos, some very pagan looking satyrs, nymphs and river gods. Pride in Hellenism seems just as strong, if not more so, than mere pride in Christianity.

As I wandered around these sites I began to wonder how much was pure Greek and how much was the product of Hellenised Berber tribes. The very name Cyrene was derived from a local berber goddess, Kura or Kurana, remembered as the guardian nymph of the spring beside the sanctuary of Apollo. Battus, the legendary first king of Cyrene and leader of the Greek colonists, is also a Berber word for "king".

The foundation myth for Cyrene is quite implicit about the role of the local Berber tribes. The first Greek settlers, having fled from drought-stricken Thera (Santorini), are urged to settle in Libya by the God Apollo. Having failed to make a success of their colony on the tiny offshore Isle of Bomba and their second settlement at Wadi Khalij, they are taken in hand by the locals. They are led up into the hills by guides who tell them: "Here, O Greeks, you may fitly dwell, for in this place there is a hole in the heavens." By which, of course, they meant plenty of rain.

I began to wonder how much had survived into modern Libya. There were some interesting indicators. The Greek name for the region, "Cyrenaica", is still in wide use, while the identities of many of the old classical cities survive. The village of Tolmeitha stands beside old Ptolemais, while Susa stands beside Sozuma (the alternative name for Appollonia in the 6th century).

I began to see Greek-Libyans everywhere. In particular, the men from coastal villages outside the ruins of Ptolemais and Appollonia looked quite recognisably Cretan. Racial identity is not an easy question to bring up in polite society, but I gradually manoeuvred the conversation and was astonished to find out that these Arabic-speaking Muslim villagers did indeed remember coming from Crete.

They laughed at my idea that their ancestors had shared a boat with Battus back in 631BC, for history has repeated itself many times since then. Their families had not been forced out of Crete by drought but by their neighbours. After the late 19th century Cretan civil war was won by the Christians, all the Muslim islanders (between a third and half of the population) were either massacred or driven out.

Some settled at Kusadasi in Turkey but many accepted the safe sanctuary offered by Libya. With a smile, one old man told me that there is no difference between them and other Libyans "except that we are better fishermen".

The easiest way to see Cyrenaica is on a guided tour. Specialist companies include Martin Randall Travel (020-8742 3355), Steppes East (01285 651010), Andante (01980 610555) and Eastern Approaches (01578 730361).

For independent travellers, there are regular direct flights from the UK to Tripoli. Booking though a specialist travel agent such as Arab Tours (60 Marylebone Lane, London W1M 5FF, 020-7935 3273), will smooth the process of acquiring a Libyan tourist visa