Thrilling, improbable, the historical city of Petra in Jordan is arguably the world's most atmospheric archaeological site, consistently delivering moments of the highest visual drama. The Treasury, first glimpsed at the end of the impossibly narrow siq, the slot canyon entrance, is just the most famous of the multitude of tomb facades that have been hewn from the orange sandstone that encloses and defines the Petra basin and its side canyons. Petra was 'lost' for hundreds of years, concealed in its desert canyon maze. Its builders, the mysterious Nabataeans, became supreme traders along the region's routes (including a spur of the Silk Road), dealing in frankincense and spices and goods from Africa. Ornate, cosmopolitan tomb facades testify to the influences of Egyptian, Graeco-Roman, Assyrian and Byzantine design. While little is known of their religion, its relics, especially its high places of sacrifice, are all around. There are two problems with getting the best out of Petra. Its fame, indeed stardom (it hosted the climax of Indiana Jones and the Last Crusade, among other media appearances), mean crowds, although they are concentrated around the main sites. And you will struggle to get round the marvels that litter this vast site: too much, in too little time. Crowds have thinned since unrest broke out in the Middle East in January, but Jordan is still a safe destination. Although there have been peaceful protests in the capital, Amman, King Abdullah is a popular monarch and he has taken measures to ease the unrest. Visiting Petra means having to do a lot of walking, so bring your boots, hat and guide book and be warned: Petra is extremely hot in summer and rainfall can spark flash floods in the canyons. Try not to come in a big group - a car and driver will give you flexibility and are easily arranged. Our driver was eagle-eyed on the road and an effective fixer. Here is my suggested itinerary for two long and fairly demanding days. You can adjust your itinerary to suit your stamina levels and the weather conditions. Day 1: Enter Petra via the eerie siq, between towering, striated cliffs peppered with shrines, water channels and Roman paving. Near the end, tiny glimpses appear of the Treasury, bright and sharp in the early sun, between the dark, cool canyon walls. Nothing will prepare you for the shock of emerging and seeing the Treasury in its full glory. Allow for five minutes of awe, then follow the main drag down the widening canyon, taking in the Street of Facades and Roman Theatre. In the main basin, follow the remarkably intact Roman paving along the Colonnaded Street, past the Great Temple, the stub of a triumphal arch and the huge walls and columns of the Qasr al-Bint, the only big free-standing building left after the earthquakes of the past two millennia. Relax over lunch in the shady grove nearby. Drink plenty, as the next bit is hard work: the processional route of more than 800 steps up a steep canyon to the tomb known as the Monastery. Through a narrow gap in the final ridge is the 3BC tomb, Petra's grandest, with its two-column storeys topped by a broken pediment and vast urn. Like the rest of Petra, it's hewn from rock. Now for the great escape: rather than returning with the crowds, walk along an oversized ledge above a 300-metre cliff for several kilometres round the mountain behind the Monastery. It is a fantastic walk, with panoramic views across a black canyon to the arid flats of Wadi Araba, although there is a scary little scramble where the path almost disappears. Next is the short walk up to the Royal Tombs in a cliff face by the main Petra canyon, passing by magnificent facades. The Urn Tomb, with a house-sized urn dominating its grand facade and portico, was used as a cathedral in Byzantine times; next along are the Silk Tomb, the Corinthian Tomb and then the huge Palace Tomb, its facade said to be the largest in Petra, with four doors and three tiers of columns. Round a corner is the tomb of Sextius Florentinus, a Roman governor. If you have the energy, follow the cliffs away from the central Petra basin, up a spectacular canyon, and then enter Petra's 'alternative' entrance, Wadi Muthlim, a thrillingly narrow and high-walled siq. A straight course through the heart of a vast sandstone massif leads to another Nabataean masterpiece, a 90-metre tunnel built to divert floodwaters from the main Petra Siq. Day 2: Begin at delightful Little Petra, a trading and supply suburb tucked into its own sandy little canyon, entered through a bottleneck one camel wide. After exploring its tombs and dining chambers, head off back toward Petra, crossing dry fields surrounded by outlandish domes and stacks. Through a gorge is a sun-baked plain. Take the central of the three gorges back down to Petra - it's the easiest, but still dramatic. As the tomb facades become frequent, rest in the shade of a large chamber and marvel at the bright, contorted stripes of its sandstone walls. After lunch, it is time for the tough climb to the High Place. The best approach is the reverse of the usual route. Clamber up a hot hillside of rubble, the earthquake-felled remains of the homes of the thousands who once lived here. After passing by simple tomb doorways in the bright orange cliff, a surprise turn up a staircase in a steep cleft leads to the beautifully carved Roman Soldier's Tomb. Opposite is the Garden Triclinium, a large rock-hewn dining chamber with three entrances. Farther up is the delicately columned Garden Tomb, then, up steps carved out of a sheer cliff-face, an imposing lion, evocative of the great gate at Mycenae. The path winds among cupolas crowning domes above cliffs, with wondrous views across the ruination of the Petra basin. You emerge suddenly by the huge platform that is the High Place. Opposite are a pair of six-metre obelisks, hewn from rock. Nearby, more than 150 metres above the main canyon, you can gaze across to a rank of royal tombs. Steps cut into a steep and dramatic cleft take you back down, giving regular thanks to the Nabataeans for their engineering skills. If you have more time, scramble up to other fabulous viewpoints, or wander some of the way down Wadi Siyagh, enjoying the tombs and open riverbed of its upper reaches. For the masochist, a fine seven-hour trek heads to the top of distinctive Jebel Haroun, with its white shrine where Aaron, Moses' brother, is said to be buried. Road to ruins Getting there Royal Jordanian airlines flies direct from Hong Kong to the capital, Amman, every Tuesday, Thursday, Saturday and Sunday. Tickets cost about HK$8,900 for an economy seat and HK$22,600 for business class. Public transport between Amman and Petra is negligible. William Mackesy lists three ways of getting to the site from Amman. By taxi You could cut a deal in Amman, but there is not much certainty about the quality of the driving and so forth. Hire a car Self-drive is not recommended as roads are dangerous for the uninitiated. Instead, many people hire a car with good local driver as part of a longer expedition, effectively organising their own mini-group. Join a tour Group tours are limiting if you want to explore in your own way and time, but many travel companies also tailor routes for individuals and small groups. William Mackesy used Petra Tours ( www.petratours.com ), a well-known local operator. He sent them his plans and they created an itinerary. For more information on walking at Petra, visit Mackesy's website, www.walkopedia.net , on the world's best walking trails.