Centuries before oil became the currency of power in West Asia and post-Ottoman Arab fraternity its lever, another commodity earned the region fortune and fame in equal measure. Its importance originated in the pagan religious rituals of biblical times and rose to a peak in the Christian era. In the pre-Islamic cartographic annals of Claudius Ptolemy, the 1st century CE polymath of Alexandria whose mastery over geography and astronomy guided expeditions of exploration and trade into the land that he described as Arabia Felix (Happy Arabia), it blazed a fragrant trail from the Horn of Africa to Babylon, Mesopotamia and Rome.

　　Upon the Frankincense Road

　　This was no metal, no mineral, no salt of the earth. Frankincense, the crystallised resin harvested from Boswellia sacra-a stunted, nondescript tree that grows wild in the rocky highlands of southeastern Arabia - commanded a price akin to gold and was venerated even more. Legend holds that when a star guided the Magi to Bethlehem, where the infant who was christened Jesus was born, they made him a gift of frankincense along with gold and myrrh (the congealed gum of another tree, Commiphora myrrha, used in funerary rites). Some biblical scholars contend that the reference to gold among the Magi's gifts is actually to golden frankincense, the most treasured variety.

　　For a measure of the value of frankincense, consider these legends. Emperor Nero, proverbially notorious for fiddling away as flames engulfed Rome, was also a pyromaniac of a different compulsion he burned at the funeral of his consort, Poppaea Augusta Sabina, the equivalent of a year's harvest of the stuff. Before his time, the tryst between King Solomon and the enigmatic Queen of Sheba, celebrated in the Song of Songs of the Old Testament, was catalysed not by fatal attraction but by commerce. The queen (unnamed in the Quranic tradition), whose kingdom some scholars have traced to the oasis of Saba in southern Arabia, is said to have called upon Solomon in Jerusalem at the head of a retinue of camels bearing - as the story goes - questions. In addition to a substantial cargo of spices and riches that no doubt included frankincense.

　　Saba, in modern-day Yemen, is not far as the hoopoe flies from Khor Rori in the Dhofar governorate of southern Oman. Here, I stood admiring the archaeological excavations at Sumhuram in a spectacular setting, overwhelmed by the immensity of time. The crumbled rock walls, restored from ruins, reconstructed an ancient fortified entrepôt that overlooks the mouth of an estuary. An inscription maintains that this was a trading port for frankincense erected at the behest of the Queen of Sheba. It is believed to be the historic port that once answered to the name of Moscha.

　　Ptolemaic scholars struck archaeological gold when the site was unearthed in the 1950s. In 1992, with the excavation of a new site near Salalah in southern Oman, Ptolemy's maps came back into the limelight. The newly discovered site, Saffara Metropolis, was the vital link between Moscha and another mysterious city known variously as Ubar or Shisr. In the Quran, it is described as a place of great wealth and fame whose rise and fall scholars have compared to that of Sodom and Gomorrah.

　　TE Lawrence, the legendary Lawrence of Arabia, came close to finding Ubar before his death following a motorcycle accident in 1935. So intrigued was he by Ubar that he called it the Atlantis of Arabia. Credit for the discovery finally went to an intrepid amateur, an American documentary filmmaker named Nicholas Clapp. A motley crew comprising fellow adventurers - lawyer George Hedges, geologist Ron Blom, maverick British explorer Ranulph Fiennes and Arabian archaeology expert Dr Juris Zarins - discovered the lost city in 1992 in one of the most hostile parts of Arabia. Their Indiana Jones-style expedition executed with gumption and panache - and helped in some measure by NASA satellite imagery - exposed the ancient caravan routes of the Frankincense Road.

　　Part of the reason why the Frankincense Road remained lost to those who sought it can be attributed, quite literally, to the sands of time. The route passed through what is today the Great Arabian Desert, an immense expanse of land in Oman and Saudi Arabia that is so meteorologically and geologically punishing that no human settlement dared to drop permanent anchor here. Well and truly bereft of modern civilisation, it acquired a name as intriguing as its character Rub' al Khali - The Empty Quarter. But time was when it was not so arid or inhospitable. In fact, the evidence is compelling that there was ample water here to support the frankincense caravans that made their way to Mesopotamia and Jerusalem. Space imagery pointed to the presence of subterranean rivers and lakes that had at some time flowed on the surface. Here, archaeologists found Greek and Roman pottery that date back 4,000 years. They also found traces of burned frankincense.

　　Standing at the ruins of Sumhuram, it is easy to shrink time to a moment, to juxtapose past and present. Feral camels graze on the shore of the estuary, nibbling at new grass with flappy lips. A fine, powdery mist leaves a film of moisture over everything. On this cruddy August morning, my small party of travellers has driven up to Sumhuram from Salalah, an hour's airhop south of the capital Muscat, which we had gladly left roasting at 47° Celsius.

　　Flying into Salalah from Muscat at this time of the year is dramatic. For the first 40 minutes of the 90-minute flight, one gazes down at the spectacular uniformity of the desert landscape crags and dunes, ridges and dust bowls. Nod off for five minutes, and the vista changes. Wispy clouds evaporate as they yield to torrid desert thermals. Southward, the clouds win, thickening into a dense foamy veil, which parts only to let the aircraft land on the rain-swept tarmac.

　　Salalah's salubrious climate, an anomaly in most of Arabia, is a gift of geography. Between June and September, monsoon winds billow into southeastern Arabia, anointing this fortunate strip of desert with highlights of green. The phenomenon, which goes by the local name of khareef, marks the beginning of the agricultural and tourism season in the Dhofar region. Salalah's homely little airport wrestles with an inordinate volume of passenger footfall. Tourists from the Gulf Cooperation Council states are the first to take joy in the rains and fill up hotel rooms.

　　We drive under purple skies beside a frothing Indian Ocean. Puddles punctuate the roads and windscreens are frescoes of semicircular smears. We have passed on our way waterfalls, hillsides cloaked in verdure, and wadis green as football fields. Starlings are nesting, weaver birds are stripping grass for their nests, bright orange fish are tippling in the clear waters of the wadi... it is hard to believe that this ululation of life is the handiwork of three months of incessant rain.

　　Rashid, our tour guide and driver, is a tall jovial Omani in his sixties. He is full of stories that he cannot complete in one telling. Midway through an anecdote, he starts a new one. Distracted by a sight on the road, he launches into yet another yarn. By the end of our two days with him, though, the raconteur has tied up every loose end, leaving us with a tapestry of tales far richer than any brocade we encountered in the souks of Salalah.

　　It is of frankincense that he loves talking the most. Rashid tells us of the asthma that crippled his childhood. "Frankincense got me back on my feet," he says, adding how his mother met a mystic from Salalah who advised her to soak a few crystals overnight in water and administer it to her son.

　　Medicine and magic charm, digestif and aphrodisiac, the virtues attributed to frankincense are several. The veneration of it seems as old as the land itself. Historians squabble over the estimated antiquity of the commerce. Some believe it dates as far back as 3200 BCE, while others agree on a more recent 1500 BCE. Either way, artefacts and potsherds recovered at Sumhuram stand testimony to these findings. These archaeological relics are preserved at the Museum of the Frankincense Land in Wadi Dawkah. It is all very impressive and humbling, but the exhibit that most fascinates me stands outside in the gravelly yard A real, live Boswellia sacra transplanted from its natural haunt in the fog oases of Dhofar.

　　As appearances go, it is disappointing. Ragged and unkempt, with an untidy mop of leaves and a scabby trunk. Of the fabled fragrance there is no sign. I crush a leaf and inhale, hungrily seeking the aroma. Nothing. I sniff at the dry flowers that rustle like potpourri in the breeze. Nothing. Then Rashid draws my attention to the trunk. The bark has been deliberately wounded in places and the oozing sap has hardened into crystals - some dark and murky, others clear and vitreous as gemstones. He pinches off a clear crystal and holds it under my nose. The aroma is unmistakable. Deep, fragrant and redolent of something sacred.

　　Later, we drive to the port of Mirbat, where fishermen are dragging six-foot sharks out of the water and packing them into refrigerated trucks headed for Saudi Arabia, where the catch is a prized delicacy. Once a prosperous frankincense port, Mirbat is today a quiet fishing village reverberating with the cries of seagulls.

　　Wild Coast of Salalah

　　Driving down the wild coast of Salalah, where until half a century ago nomadic tribes took refuge in caves, Rashid shows us Al Mughsayl. The limestone cliffs along this unbelievably scenic shore have been eaten hollow by salt spray and water. As the breakers whipped up by the monsoon crash on the shore, jets of seawater squirt like fountains from the blowholes, drenching happy holidaymakers who scream for more.

　　There's time to kill before sundown, so we spend it drinking copious quantities of weak but refreshing kahwa coffee and snacking on strips of stone-grilled camel meat at a street side shack. It doesn't matter that over a late lunch we had gorged to bursting on beef shawarma and mandi - the traditional southern Arabian dish of roasted chicken and saffron rice.

　　Dusk is the perfect time to visit the Frankincense souk in Salalah. It is a medieval place straight out of the Arabian Nights. Smoke rises in plumes from censers, and the fragrance of frankincense is pervasive. Wholesalers and retailers, itinerant vendors and cart pushers are all selling frankincense in some form. The crystals, sorted by grade, are marked with price placards. Medicated oils, floor cleaners, disinfectants, cosmetics, toothpastes, wall hangings, fridge magnets - there's plenty to ogle. As in any market in Arabia, the habibi method of polite haggling always gets you a sweeter deal.

　　Centuries ago, after the Roman Empire declined and Christendom renounced pagan rituals, the hunger for frankincense weakened. The desert conspired, too, enveloping great parts of the Frankincense Road and burying it under a sea of sand. Frankincense remains special to the Omanis, but the price it commands is far from astronomical. Today, one can take home a kilogram of it for about 10 Omani rials. But that ethereal fragrance... nothing can put a price on it.

　　The Information

　　Getting There

　　Salalah can be reached via Muscat on Oman Air, which operates 91 direct flights a week to Muscat from Bengaluru, Chennai, Delhi, Hyderabad, Jaipur, Kochi, Kozhikode, Lucknow, Mumbai and Thiruvananthapuram. Air India, Air India Express, Indigo and Jazeera Airways also fly to Muscat from Indian cities. Roundtrip economy fares from Rs 38,000.

　　Visa

　　Indian nationals must apply for a tourist visa through a travel agent that will liaise with an Oman-based travel partner to arrange a package inclusive of visas, hotels, sightseeing, activities and transfers. Fees OMR 20 plus processing charges. Processing time 4 - 6 working days (Fridays and Saturdays are holidays). Valid for 30 days from entry (www.rop.gov.om).

　　Where to Stay

　　The capacious and luxurious Salalah Rotana Resort is arguably the best address in Salalah. With three themed restaurants, a well-stocked bar, pool and private access to the beach, it is a great stay option in and out of season (from OMR 66 www.rotana.com).

　　What to See & Do

　　The Museum of the Frankincense Land in Wadi Dawkah has a great collection of historic relics, but could use more interpretation. It also has a few Boswellia sacra trees (Al Balid, As Sultan Qaboos St, Salalah entry fee OMR 2 open from 8am-2pm and 4-8pm Sat-Wed, 4-8pm Thu and Fri). Taqah Castle is a bit of a drive from the city, but offers a commanding view of the countryside and a look at some interesting artefacts. A morning visit to the archaeological sites of Al Balid and Khor Rori at Sumhuram sets the perfect tone for exploring the Frankincense Trail. The fishing port of Mirbat is best visited in the evening. Nature buffs and photography enthusiasts will enjoy visiting Wadi Darbat for its scenic rain-fed watercourses and Al Mughsayl beach for the blowholes.