Petra and the Siq: How the Nabataeans Carved a City From Rock

^{HOW A CARAVAN KINGDOM CUT ITS CAPITAL INTO THE ROCK AND KEPT IT SUPPLIED WITH WATER IN THE DESERT}

Petra, in southern Jordan, was the capital of the Nabataeans, an Arab people who grew rich on the caravan trade between Arabia and the Mediterranean. UNESCO describes the city as half built and half carved into the rock, set among mountains cut through by passages and gorges. Its main entrance is the Siq, a winding natural cleft just over a kilometre long, which opens onto Al-Khazneh, the Treasury, a façade 39.5 metres high cut directly into the cliff. Petra stands in an arid basin, and its population depended on dams, rock-cut channels, tunnels and cisterns that collected rainwater and kept flash floods out of the city. The kingdom was absorbed by Rome in 106 AD, the city was damaged by earthquakes in 363 and 551, a Swiss traveller made it known in Europe in 1812, and UNESCO inscribed it as a World Heritage Site in 1985.

^{WHO WERE THE NABATAEANS AND HOW DID TRADE MAKE THEM RICH?}

The Nabataeans were nomads from northern Arabia who had settled in southern Jordan by 312 BC, according to the Metropolitan Museum of Art. In that year Antigonus I Monophthalmos, a former general of Alexander the Great, tried and failed to conquer them, and Petra, known in antiquity as Raqmu, was already the centre of their territory. Over the following centuries the kingdom expanded. Aretas III (r. 86 to 62 BC) pushed north and briefly occupied Damascus before Roman legions under Pompey halted the expansion in 64 BC. At various times Nabataean rule covered parts of modern Jordan, Syria, northern Arabia and the Sinai and Negev deserts.

The kingdom reached its height under Aretas IV, who ruled from 9 BC to 40 AD. The Met describes Petra in this period as a cosmopolitan trading centre with a population of at least 25,000. Its reputation travelled as far as Han-dynasty China, where the city was recorded as Li-kan. Petra's wealth came from its position. UNESCO places the city between the Red Sea and the Dead Sea, at a crossroads between Arabia, Egypt and Syria-Phoenicia, and describes it as a major caravan centre for incense, silks and spices in Hellenistic and Roman times. The Met adds that the kingdom sat at the northern end of the caravan route from South Arabia to the Mediterranean, linking Petra with goods from China and India as well as Arabia.

The incense itself came from the south of the Arabian Peninsula. UNESCO's separate listing of the Incense Route, four Nabataean desert towns in the Negev inscribed in 2005, describes a trade carrying frankincense and myrrh from Yemen and Oman to the Mediterranean, with its main line running from Petra to the Mediterranean ports. That trade flourished from the third century BC until the second century AD. The Negev towns relied on dams, channels, cisterns and reservoirs to support large-scale agriculture, the same set of techniques the Nabataeans used at their capital. Profits from this trade paid for the rock-cut tombs and temples that the Met notes combine elements from Egyptian, Mesopotamian and Hellenised Western architecture.

^{THE SIQ: PETRA'S ENTRANCE GORGE}

The Petra Development and Tourism Region Authority describes the Siq as a passage just over a kilometre long, formed naturally when the mountain split and leading to the Treasury. The Nabataeans paved a road through it at a lower level than the present one, and after annexing the kingdom in 106 AD the Romans repaved the central route. Two water channels run along both rock sides of the gorge, and the gorge contains Nabataean baetyls, or sacred stones, including a niche carved with two of them.

The Siq was also a flood risk. Before its entrance the Nabataeans built a dam across the mouth of the gorge in the first century BC and cut an 82-metre tunnel through the rock to redirect the water through Wadi Mudhlim, from where it fed reservoirs, cisterns and further dams. The present dam at the Bab as-Siq was built in 1964, over the larger Nabataean original, after a flash flood swept through the gorge. UNESCO still lists flooding through the Siq as a threat if the diversion system is not maintained.

^{AL-KHAZNEH, AD DEIR AND PETRA'S ROCK-CUT ARCHITECTURE}

Al-Khazneh, the Treasury, is dated by Jordan's Petra Development and Tourism Region Authority (PDTRA) to between 60 BC and 50 AD. It stands 39.5 metres high, and many archaeologists believe it was the mausoleum of Aretas IV. Its façade shows the Hellenistic influence on Nabataean design: six Corinthian capitals carry a frieze of winged griffins and vases among scrolls, and the goddess Isis stands at the centre, surrounded by dancing Amazons holding axes. The name comes from a Bedouin legend that a pharaoh hid treasure in the urn at the top, and the urn still carries bullet marks from attempts to break it open. In 2004 three Nabataean tombs dating to the end of the first century BC were found beneath the monument.

Ad Deir, the Monastery, is larger. Its façade measures 47 metres wide by 51 metres high and is believed to date from the early second century AD, in the reign of King Rabbel II. It follows the Treasury's model, but niches that once held sculptures replace the relief carving. An inscription nearby suggests it was dedicated to the deified king Obodas, and the hall was probably used for meetings of religious associations. It was later reused as a Christian chapel, with crosses carved into its rear wall, which gave it its Arabic name, dayr, or monastery.

^{HOW DID THE NABATAEANS MANAGE WATER?}

Petra receives about six inches (roughly 150 millimetres) of rain a year, according to the American Society of Civil Engineers, which lists the city's water system as a historic civil engineering landmark. Despite that, ASCE estimates the city supported 30,000 to 40,000 inhabitants. UNESCO credits an ingenious water management system with making extensive settlement possible in an essentially arid area through the Nabataean, Roman and Byzantine periods.

The system combined capture, storage and defence. Canals were cut into solid rock and fitted with piping, an aqueduct and tunnel carried water across the site, and reservoirs and cisterns stored it through the dry months. Particle-settling basins cleaned the water before use. Diversion dams and the tunnel at the Siq protected the city centre from floods coming down the Wadi Musa basin. ASCE notes that because Petra sat on major trade routes, the Nabataeans could adopt Greek and Roman hydraulic technology and combine it with their own conservation methods, building and extending the network between about 400 BC and 400 AD.

^{ROMAN ANNEXATION, EARTHQUAKES AND DECLINE}

In 106 AD the emperor Trajan incorporated the Nabataean kingdom into the Roman province of Arabia. Petra continued as a city, and UNESCO lists its Graeco-Roman remains: a colonnaded street, a triple-arched gate, a theatre, a nymphaeum and baths. Excavations by Brown University at the Great Temple, a precinct founded in the last quarter of the first century BC, have traced its history phase by phase, including the Roman takeover, the building of baths and an earthquake in 113 or 114 AD that narrowed the temple's doorways and corridors.

The earthquake of 363 was more destructive. The Brown excavators describe it as the most powerful blow to the Great Temple site, collapsing its propylaeum and colonnades. Petra was still occupied in the Byzantine period, when a triple-apsed basilica was built and the Urn Tomb was converted into a church, but the earthquake of 551 left what the excavators call a more impoverished community and ended the Great Temple precinct. At the temple, the late Byzantine period that followed, to around 640, was one of abandonment and robbing. Crusader fortresses were later built at Habis and Wueira, and a mosque stands on Jebel Haroun.

^{BURCKHARDT IN 1812 AND THE UNESCO LISTING}

Petra entered European scholarship through Johann Ludwig Burckhardt, a Swiss traveller born in 1784. The African Association had commissioned him to cross Africa to the River Niger, and he studied Arabic in Cambridge in 1807 to 1808 before travelling through Syria, Palestine and Arabia as Sheikh Ibrahim Ibn 'Abd Allah. On 22 August 1812 he reached Petra by claiming he had vowed to sacrifice a goat in honour of Haroun (Aaron), whose tomb UNESCO places on Jebel Haroun. He got as far as the Qasr al-Bint before his guides grew suspicious and he cut the visit short. He described it in his diary, published as Travels in Syria and the Holy Land, and died in Cairo in October 1817.

UNESCO inscribed Petra on the World Heritage List in 1985 under criteria (i), (iii) and (iv). The property covers 26,171 hectares, matching the boundaries of Petra National Park in Jordan's Ma'an Governorate. It includes far more than the Nabataean city: Neolithic Beidha, Iron Age Umm al-Biyara and Chalcolithic copper mines at Umm al-Amad. The main conservation threats UNESCO identifies are wind and rain erosion of the carved façades, flash flooding through the Siq and tourism, which it says has increased greatly since inscription, with congestion concentrated in the Siq itself.

^{W AMMAN AND THE SIQ AS AN ARRIVAL SEQUENCE}

W Amman opened in April 2018 as the W brand's first hotel in Jordan, and Silverfox Studios designed the full interiors of the 40-storey hotel. The design draws on two landscapes: the rose-toned rock formations and canyon of Petra, and the limestone hillside city of Amman. Petra lies about 160 miles (around 260 kilometres) south of Amman, and its approach through the Siq, a narrow gorge just over a kilometre long that ends at the Treasury, is the reference for how guests enter the hotel.

The arrival, called the "Canyon Walk", recalls the Siq, with angled planes and lines of light leading guests to the lifts and lobby. Movement through the rest of the hotel is planned as a "Journey of Discoveries", shaped around canyon and shard forms, and the faceted, shard-like façade carries the same idea to the exterior.

SOURCES

1. UNESCO World Heritage Centre Petra
2. UNESCO World Heritage Centre Incense Route: Desert Cities in the Negev
3. The Metropolitan Museum of Art The Nabataean Kingdom and Petra
4. American Society of Civil Engineers Petra
5. Petra Development and Tourism Region Authority The Siq
6. Petra Development and Tourism Region Authority The Dam
7. Petra Development and Tourism Region Authority Al Khazneh
8. Petra Development and Tourism Region Authority Ad Dair
9. Brown University, Petra Great Temple Excavations Petra Great Temple excavations report
10. University of Cambridge The man who discovered a lost wonder of the world