Turn left for Carthage
We're standing at a crossroads in the centre of a seaside city facing the Mediterranean. Even in late autumn the sun is fierce and the sky a boundless blue. "Turn right here," says the guide, "and the road will take you all the way to Alexandria. Turn left, and you will end up in Carthage."
That ancient name is the clue. For this city is Leptis Magna in present-day Libya.
Raised to its glory by Septimus Severus, a local boy who became emperor of all Rome, this magnificent metropolis was the gateway for trade between the Roman Empire and the rest of Africa. The wild beasts and grain that fed the Roman appetite for bread and circuses sailed from this port to amphitheatres throughout the empire.
Apart from our 11-strong group, aiming to see the sites of old Tripolitania in a long weekend, the vast city, once home to 100,000, is deserted. The baths, the shops and markets, the amphitheatre that holds 16,000, the circus next door where 23,000 would cheer on the charioteers, are silent.
Libyans are only interested in more recent history, according to Yousef Khatali, our excellent guide to old Tripoli and the ruins of Sabratha on the first day of the trip.
As Yousef whizzes us round the Jamiahiriya national museum in the Red Castle in the centre of Tripoli, past gorgeous statues and mosaics so detailed that a pointillist would envy the effect, his witty asides on the workings of modern Libya are as fascinating as the history he is outlining.
This is the man who showed television history pundit Dan Cruickshank the treasures of the country. If there were any justice Mr Khatali would have his own TV series. With a wry smile, he points out a battered, duck-egg blue VW Beetle that is, he says, "the most important item in the museum".
Popularly known as "Gaddafi's camel", this vehicle belonged to Libya's current ruler, who deposed the former king in 1969, and claimed a victory for the nomadic peoples of the desert. Outside the museum, giant portraits of the Libyan leader hang between the plain green national flag that flutters everywhere.
Yousef takes us under the massive arch of Marcus Aurelius into the old town, showing us mosques and grand houses. Later, in Sabratha, as we test out the acoustics of the beautifully restored Roman theatre, we ask Yousef why there are no performances on the site today. He quotes what the Colonel said on taking power: "The tent has triumphed over the castle and the shepherd has beaten the king," adding his own coda: "What use have nomads for theatre? What use is orchestral music to shepherds?"
Libya is a Muslim state. So, although the open-air cafes of Green Square in the centre of Tripoli are buzzing late into the night, coffee is the strongest drink on offer. But that coffee is good, perhaps in part thanks to last century's Italian occupation, and the food is fine in Tripoli, perhaps less so outside the capital.
Our travel company, Explore, seems to have a sixth sense about matching room-mates, which makes it a good choice for a single traveller, although there were also couples and pairs of friends in our group. I got on famously with Anna, an extreme-driving instructor and photographer. Another pair bonded over a late-night sparkly-shoe-buying expedition in the town of Zlitten, as the rest of us sat around after dinner discussing what we would drink if we could. This is not a conversation that can be sustained for long. I had gone to Libya to see the Roman ruins; I hadn't realised I'd get a detox break thrown in.
Another surprise for women who have had unwanted male attention while travelling in other parts of North Africa is how relaxing it is here.
Shopping late at night in the medina in Tripoli with two blondes, no one bothers us.
The trip includes a second day in Leptis Magna. Having "done" the site on the first day, I wondered if this was necessary, but it proves a masterstroke. Left to our own devices, we scatter on separate voyages of discovery, occasionally bumping into each other and recommending our favourite parts of the city, and making a forbidden foray into the outlying Hunting Baths, still half-hidden in the sand.
That should be the highlight, but our young guide ("I'm called Yasser - like Arafat") has one more card up his sleeve, taking us to the fabulous Villa Silim on the way back to Tripoli. The guard unlocks the gates just for us, and we are free to wander from room to room of this Roman des res by the sea. Driving back into Tripoli amid the Ramadan rush at sundown we are overtaken by a pick-up truck. In the back sits a camel, poised as a duchess in a limo. It feels like a symbol of modern Libya, but quite what it means will take more than a weekend trip to find out.
Explore's Leptis Magna Weekend, from the Adventure Breaks brochure, departs October to April. Prices from pound;615 pp include return flights from Gatwick, all transportation, three nights' BB accommodation, one night's half board, local payments and the services of a tour leader (www.explore.co.uk; 0870 333 4001)