You might be thinking that I'm not going off-piste at all - that I am, in fact, on a well-trodden piste as an archaeologist writing about living and working in the Middle East and North Africa. Just part of the job, really. But no, it's not like that. When I go to strange lands, I'm far removed from my own digging grounds. And the ruins of caravan cities that lure me year after year serve to switch on my aesthetic, rather than my professional, passions.

Yet today, when anyone can travel anywhere, and when everyone with a fondness for archaeological souvenirs can be a cultural tourist, it may be difficult to understand what I mean by my travels. They are certainly not visits to Petra or Palmyra for the day, with perhaps a night or two spent at a comfortable new hotel just off site; nor hardship journeys into remote areas still untravelled or hardly explored (usually with good reason). Rather, they examine the somewhat unfashionable notion that if you spend months at a time at one place, you can dig deeper, reaching beyond the tourist image towards its genius.

The reality of this travelling does mean accepting, if not especially seeking, the unpleasantness of an often-uncomfortable billet. But it's a fair trade-off to be on site in the empty moonlight, walking through temples in the utter stillness of the night and coming close to the unsayable.

There are some travelling rules, though, that I've learnt from living in Mediterranean lands - my own near-abroad - for more years than I ever lived at home.

É«ºÐÖ±²¥

"There are two things you don't need in an Arabian land," the Dutch Ambassador once told me. "Your heavy winter coat and the word why. Hang them both on a coat rack and leave them behind."

Despite the high authority of His Excellency, the former ambassador to Bahrain, Beirut and Tehran, I have never listened to this advice. Perhaps because the why of things is a driving force in my life - it underlies my urge to travel, to cross chancy borders and to plonk myself down at the edge of another society, daring myself to become part of those bewitching lands: Egypt, Jordan, Syria, Lebanon, Libya.

É«ºÐÖ±²¥

Never have I asked why as often or as wistfully as in Libya. The question received an answer of sorts in a huge concrete block of a hotel sited in an overgrown village, 800km from Tripoli and almost as far as you can get from the inhabited world. Larger-than-life portraits of the Great Leader, Muammar Gaddafi, covered the walls. Lunch was in a monstrously grand dining hall with rococo chairs, plastic flowers on every table and bowing waiters. For whom? Not a soul sat there but a Dutch artist, an archaeologist and our driver.

"Why was this hotel built here?" I asked.

The driver replied knowingly: "Just in case."

This cryptic statement became my travelling leitmotiv. In the Arab world, you never know if you'll get your visa, if a minister will grant permission, or if the smiling colonel will always smile with you over tea. Never knowing, you'll be ready for anything, just in case.

"Pass the condiment tray," I said to the Dutch artist, my travelling companion, as I looked at the brown sludge quivering on my plate. It was Egypt during the winter of 1983-84. We had made ourselves at home at the Hotel Habu (now lamentably closed), in two rooms on a terrace overhanging the massive enclosure walls of Medinet Habu in a deserted West Thebes. From this height, I spent hours trying to catch the reliefs of Rameses III in the shifting of the light. The sharp sun made these walls dark; and out of this darkness, new forms constantly emerged.

Never travel without a condiment tray. However dispiriting the boiled camel meat or quivering sludge, there's nothing that can't be improved with a condiment tray: abundant garlic, sambal oelek (Indonesian chili and lime sauce), sambal udang (chili, oil, garlic and crushed shrimp), sambal badjak (the darkest there is, just like it sounds), and lime oil pickle. And Dutch water. Wherever you go, bring Dutch water (also known as genever). Even to Libya. Especially to Libya! But also for a nip at the roadside stalls with burnt unspeakable bits on the fire - when you need all three sambals and an added slug of crystal-clear NL H2O.

Once, just outside Petra, we celebrated having survived three months alone in Nazal's Camp, a wonderful crumbling edifice, monastic in austerity and a good deal dirtier - a memorable winter of paraffin stoves, snow on the hills and distant wolves. A new restaurant was still in the project stage and would open, the owner averred, as soon as they fixed the plumbing; but for us, anything! So we ate roast lamb seated at a table and on real chairs, while on either side open sewers went sloshing through the soon-to-be dining room. This was nothing that NL H2O couldn't fix, and I still don't remember how we made it back to camp.

That was 1990. We had moved to Nazal's Camp to escape the goats. I needed to remind myself of the goats whenever, as was often, the generator sputtered and the lights went out. The previous year, we had rented a house in the Bedouin village of Umm Sehun, high above Petra. Instead of rent, we paid the village chief, the muktar, to repair the roof and walls and install kitchen and sanitary facilities - the latter a contradiction in terms as the bathroom was the preferred cooling-off spot for the muktar's goats; there was no glass in the windows. As a rule, too, they were fed, loudly farting as goats will, on the terrace outside the bedrooms.

So we were now alone all winter at the end of the Roman road, nearly dwarfed by the massive Kasr el-Bint, temple of the god Dushara. We sat on his vast altar in companionable silence while the guards emptied the site of visitors, and twilight came.

When the Nabataeans began to build in Petra, they hacked the fabric out of the hillsides in such a way that the structures emerge from the sandstone as if they are part of the mountains themselves. Their theatres, houses, palaces, temples, tombs and the columns and pillars of their antechambers are all carved out of the same living rock.

É«ºÐÖ±²¥

It is a city of many colours. You walk over veins of red, white, yellow and blue, with stripes of purple or violet here and there. Small wonder that the Nabataeans knew their city as Raqmu, "the many-coloured"; it was the Greeks who called it Petra, "the rock". Both names are truths.

Two millennia ago, for the briefest historical moment, caravans came down these roads on their interminable way from China to Rome. The caravans arrived on the fringes of Western history only after taking to the sea off the Indian coast: two drawn-out routes of silks and spices, one coming to embellish Petra, the other to make the desert bloom at Palmyra.

In Palmyra, we found ourselves at the archaeological dig-house within the sanctuary of the Temple of Bel. This, too, had once been a muktar's dwelling, a handsome building surrounding a courtyard planted with date palms and terebinth trees; from the terrace the ruins spread out in front of us, and its other side looked out over the remains of the oasis.

É«ºÐÖ±²¥

We were lucky. When we first arrived in February, we were the only visitors and so could take all three rooms over the courtyard facing west, keeping the afternoon sun for ourselves. In the dig-house, we had a house servant who spent his days watering the garden and spying on our every move. This was a time when faxes were forbidden in Syria because the mukhabarat (secret police) hadn't figured out how to read them, as they were required to do with all foreign letters. Of course, our servant knew no Dutch - it was our secret language. In English, we used codes. We would never refer to the unmentionable Zionist entity by name - that could cause trouble - but to "Dixie" (the other side of the Mason-Dixon line) or "across the big J".

Occasionally, there were other guests, classicists or archaeologists. Grateful as we were for conversational company, we nonetheless put a lock on our shower and toilet door; yes, we expropriated it. It was Dutch-cleaned, and I have stayed in too many dig-houses to be charitable.

On 6 April 1996, the ancient Babylonian New Year, with a full moon looking down on us, we sat in the Temple of Bel reading aloud from the Epic of Creation: "When skies above were not yet named/Nor earth below pronounced by name."

Illuminated by our candles, we sat in the high south chapel, reached by means of a purloined ladder.

The next year was remarkable for the two-tailed comet that hovered every night over the Temple of Bel until the very last weeks of our stay. Sitting on the terrace of the dig-house, staring out at the utterly dark and silent temple, it was easy to think of portents, and how the cosmic indifference of Hale-Bopp would once have foretold the death of kings and the fall of empires. We could almost reach out and touch that ancient world, when every sign was meaningful.

Leaving Palmyra in late 1998, as once freight-laden camels began the next lap of the Silk Road, we climbed up the Beq'a Valley to the temple city of Baalbek, set in a wide valley beneath snow-capped mountains, with cool rivulets of water and perpetually bubbling springs. The city of the Sun: Heliopolis. The vast temples of Baalbek, constructed in the course of the first two centuries of our era, were given over to Roman gods - Jupiter, Venus, Mercury - strangely transplanted to the highest ridge of the Beq'a. It is remarkable that, even after 1,000 years of Greek and Roman rule, Baal's name and dignity would return to his ancestral city.

In the end, a journey matters for the friends we meet - warm friendships that do not grow from dropping in, but from returning. At Baalbek one night, our friend Haris exclaimed about our staying there: "Just a few of us stayed on in the years of war when almost nobody was here: drug dealers; some arms dealers; everybody else who could went to Europe or America; a few come back now, but Hezbollah ... you know."

Of course Baalbek, after 25 years of Lebanon's civil war, has added a strange tone to its beauty, like the light of a dead star. We are not fools. Baalbek is the headquarters of Hezbollah, and renting a house and staying there, two women alone, warranted careful consideration. But learned Western women and artists in the Middle East have the status of honorary men, seen as strong but aberrant - a third gender, possibly. Nonetheless, whether empresses or charladies, whatever women do, in the Orient they are still women. So our good friend Hikmet, a journalist with an inside track to Hezbollah, would be our early-warning system ("just in case"): if we were no longer safe, we would expect a telephoned "pack up and get out quick".

We always listened to the BBC World Service. "No news is good news" when it comes to Baalbek, Lebanon or even Dixie for that matter. We may have been listening to "world radio", but the BBC programmes were sporadically interrupted by flashes of a male voice reciting over and over: "Charlie, Bravo, Charlie, Bravo, Tango, Charlie, Bravo, Tango." Perhaps that was why, when the attack finally came, we were taken by surprise.

We had rented a house in what was once the Christian quarter of the town, overlooking some still-standing columns of the garbage-strewn Roman forum. Big and airy, but badly decayed, a house left to rot since its sale for a peppercorn when the Christians packed up and left. We made it habitable.

Work and study were punctuated by distant shellfire. I learnt willy-nilly to identify that famous artillery "crump", and the Israeli Air Force's retaliatory "ga-boom". Bombs fell one night in the Beq'a, about 25km from us, outside a Jesuit monastery, over the walls from its agricultural college, where they teach the care and feeding of 195 Dutch cows. Ten Hezbollah fighters were killed when Israeli smart bombs hit their base, so close that the cows stopped giving milk. Sensible animals! If only others would go on strike against such tit-for-tat slaughter - a kind of mooing Lysistrata.

One night we were shaken out of bed by explosions. Grasping a bottle of French cognac, we sat outside on the terrace hearing the Israeli jets on their way to the electricity plant 1km outside the town. The house shook when they hit their target and fireworks lit up the sky as Hezbollah responded with wild anti-aircraft fire from weapons everyone knew were hidden in the city's garbage dump. The display went on for an hour or more. The cognac finished, we went to bed. The Dutch Ambassador was not pleased that we had watched the show outdoors. "Young ladies," he scolded, "what goes up can come down."

A few days later, we drove past Hezbollah headquarters, a dim complex of buildings with black flags flying, next door to an ice-cream shop in the centre of town.

É«ºÐÖ±²¥

"Why?" I asked the Dutch artist.

"Put it back on the coat rack," she said.

Cicero says somewhere that there is nothing whatsoever so beautiful that our imagination and our mind cannot conceive of something still more beautiful. And he is right: We surely can, and it's over that hill ... and in the next country.