"Wow," exclaims the visitor from New Zealand, a place, after all, with a human history shorter than most. For from a wooden walkway we’re gazing down at an archaeological site of giddying age. Built about 9000 BC, it’s more than twice as old as Stonehenge or the Pyramids, predating the discovery of metals, pottery or even the wheel. This is Göbekli Tepe in south-eastern Turkey, generally reckoned the most exciting and historically significant archaeological dig currently under way anywhere in the world, and there are neither queues nor tickets to get in.

Wow for a number of reasons, then, though it’s neither the access nor the staggering implications of the site’s age that has particularly impressed the man from distant Auckland. Neolithic Göbekli Tepe is also remarkably beautiful. From the partially excavated pit rise circular arrangements of huge T-shaped obelisks exquisitely carved with foxes, birds, boars and snakes or highly stylised human attributes including belts, loincloths and limbs. We’re profoundly moved by this glimpse into a radically recast prehistory, and mystified too. Even the archaeologists hard at work on this September morning can only speculate about its function, not least because the stones appear to have been deliberately buried.

“This series of sanctuaries is the oldest known monumental architecture,” explains the excavation leader and approachable on-site presence Professor Klaus Schmidt. “Maybe burial was already part of their concept from the very beginning.”

Two years ago a bare trickle of visitors found their way to this remote hilltop revelation. Now, however, visitors are building their entire itineraries around Göbekli Tepe, surest of shoo-ins for future World Heritage Status, and foundations are already in place for a protective site canopy, a nearby visitors’ centre and a ticket office. Numbers are set to explode here, the more so because the surrounding Euphrates region centred on the ancient cities of Gaziantep and Sanliurfa happens to boast an exceptional wealth of cultural draws.

It helps that another spectacular summit monument, the vast stone heads in honour of Roman-era King Antiochus on nearby Nemrut Dagi, has figured prominently on must-see lists for decades. In recent years, however, there have been further momentous discoveries such as the mosaics at Roman Zeugma, which were rescued from the rising waters of the dammed Euphrates before being installed in the magnificent new museum at Antep – the locals don’t bother with the “Gazi” prefix – in 2011.

With major restorations across Antep’s historic centre and its burgeoning reputation among foodies, not to mention another substantial mosaic find at Haleplibahce in the centre of Urfa (again, no prefix), it’s perhaps no surprise that the region’s proximity both to Turkey’s troubled border with Syria and to adjacent areas of Kurdish unrest are doing little to dampen down interest.

Antep, despite the fatalities caused by a recent car-bomb blamed on Kurdish separatists, is awash with Western visitors. I pass them in the high-walled alleys of the old city where the painted plaques above the doors announce the owners as honoured hacis, or pilgrims, to Mecca. All over a city knee-deep in development money overflowing from Euphrates dam projects, masons spectral with stone dust are restoring mosques and the gated artisans’ arcades known as hans. Not that the tarting up has leached anything of Antep’s famous atmosphere. In grimy ateliers, copper workers hammer patterns into decorative platters, and sparks fly from the spinning stones of the knife sharpeners. On Crazy Sheep Street, shawled women are buying red peppers by the sackload and hauling them off to the alleys outside their front doors where they and their neighbours squat to hull them for a spicy cooking paste called salça. The lanes are fronted with baskets of spices and nuts, especially locally grown pistachios, the symbol of the city and the star turn in its distinctive “meat and sweet” cuisine; nowhere has a higher density of baklava-style pastry shops, from huge salons to tiny deli counters, than Antep.

I dine at a cavernous institution called Imam Cagdas, a kebab and baklava diner with wipe-down menus, sweep staircase and waiters in traditional monochrome. The traditional starter, a mince-topped pizza-style flatbread called lahmacun, is followed by a superior kebab – mine is rich in garlic and pistachio – washed down with ladles of sour-yogurt ayran. I move on to a plate of baklava before being tempted into another pistachio pudding, fistik sarma. Overload. The good news is that my lodgings at Anadolu Evleri, a collection of town houses with shabby-chic rooms arranged around a high-walled courtyard, are just next door.

So next morning to the city’s new Zeugma Museum, a stunning ensemble of light and space that confirms the extent of Antep’s civic ambitions. This world-beating collection of second-century Roman mosaics, rich in geometric pattern and mythological detail, are displayed from a range of perspectives including raised walkways and mezzanines, and with other retrievals from Zeugma such as frescoes, fountains, columns and statues. It’s a collection all the more poignant for the fact that it acknowledges the considerable thefts suffered in the course of the Zeugma excavations, with projected images filling in for the illicitly lifted mosaic sections. A low-lit labyrinthine corridor leads to the standout mosaic, the so-called Gypsy Girl, whom experts have more accurately identified as a Dionysian maenad; a party girl, in short, if her eyes – which even after all this time spell nothing but trouble – are anything to go by.

We take the road east to visit what remains unsubmerged of Roman Zeugma – a fine villa, complete with frescoes and mosaics – though my eye is drawn to the shimmering lake that once was the Euphrates. The road continues through pistachio orchards to the half-drowned town of Halfeti, where the few townsfolk that remain now offer nostalgia-tinged boat trips over their submerged homes and orchards.

The new topography is beautiful though surreal, and full of bizarre adaptations like the raised duckboards that have been fitted so that the mosque may continue to function. “Worship here is permitted,” a sign on the door confirms, “but swimming in the mosque is forbidden.”

At sand-coloured Urfa we are on the edge of Arabia. To their owners’ whistles flocks of homing pigeons rise from flat-topped roofs hung with lines of drying aubergines in the early evening. Beneath the crusader castle families walk by the sacred ponds and the shaded tea gardens that mark the cave where Abraham is said to have been born.

In the grand yards of the mosques clustered in the honour of a prophet sacred to all three monotheistic religions, men in shirt sleeves and in Arab turbans gather to wash at the fountains; flocks of women from lands to the south pass in all-over black but for the gold jangling at their wrists. Beyond the gardens I wander into Urfa’s labyrinthine bazaar, an exotica of turnip juice stands, stalls serving fried liver, pigeon traders and cot makers.

In the morning Mehmet, a local archaeologist, leads me beyond the sacred ponds to the Aleppo Gardens (Haleplibahce) where the city’s own mosaics are on display in situ. The centrepiece of these recent finds is the so-called Amazon Villa. The best of these fifth-century mosaics – a pictorial life of Achilles, and a magnificent rendering of an African native and zebra – are exquisitely suggestive of another time in the rich and varied history of this frontier city. Then Mehmet points beyond the villa where a site is being cleared for a major new archaeological museum, one that no doubt means to match anything rival Antep can do.

The rush is on; in just two years’ time, little-known cultural attractions like the mosaics at Haleplibahce and the obelisks at nearby Göbekli Tepe are slated to be firmly established on the tour bus itineraries. By then, however, who can say what other treasures will have turned up in this history-rich corner on Turkey’s Kurdish and Arabian borders?

Packages

Jon Baines Tours (020 7223 9485; jonbainestours.co.uk) has a two-week “Ancient Anatolia and the Origins of Belief” tour led by Lavinia Byrne departing September 15 at £2,580 pp.

Steppes Travel (01285 880980; steppestravel.co.uk) offers a five-day tailor-made tour from £1,250 pp.

Travel the Unknown (020 7183 6371; traveltheunknown.com) has nine-day trips departing September 2013 and May 2014 from £1,895 pp plus flights.

Eastern Turkey Tours (easternturkeytour.org; 01792 293464) 8-day 'Ancient Cappadocia to Gobekli Tepe' tour has four departures this year from Ankara and costs £1020pp h/b not including flights.

Getting there

Regular flights to Gaziantep and Sanliurfa via Istanbul through Turkish Airlines (0844 800 6666; thy.com, from £260 return) and Pegasus Airlines (0845 0848980; flypgs.com, from £120 one way).

Where to stay

Anadolu Evleri, Gaziantep. Delightful historic haven with characterful rooms in high-walled courtyard (0090 342 2209525; anadoluevleri.com: b & b doubles from £75).

Cevahir Konukevi, Sanliurfa. Restored mansion, with roof terrace for dining, often with live traditional music (414 2159377; cevahirkonukevi.com, doubles with breakfast from £130).

Visas

£10, payable on entry.

Reading

Eastern Turkey (Bradt, £16.99) offers the best coverage, though recent changes means major omissions including Göbekli Tepe.

Further Information

Turkish Tourist Office (0207 839 7733; gototurkey.co.uk).

Gaziantep-based Arsan (342 220 6464; arsan.com.tr) for local tours, guides and drivers.