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The Rub’ al-Khali, or Empty Quarter, is the world’s largest sand sea and one of the most inhospitable regions on the planet. Inspired by Wilfred Thesiger’s classic travelogue Arabian Sands, photographer George Steinmetz has travelled to the Arabian Peninsula three times during the past decade, using a motorised paraglider to capture the beauty of the shifting sands below

Above Rub Al Khali

A rocky peak in Yemen that forms part of a mountain range between Marib and Bayhan al Qisab, used over the centuries as a hideout for smugglers, criminals and terrorists. Not always successfully: in 1992, a CIA plane blew up a truck carrying al-Qaeda operatives through the area. The Marib province sits on the southern edge of the Rub’ al-Khali, or Empty Quarter. The world’s largest sand desert, the Rub’ al-Khali covers around a fifth of the Arabian Peninsula and stretches into four countries: Saudi Arabia, Oman, Yemen and the United Arab Emirates (UAE). The entire desert is larger than mainland France, measuring around 583,000 square kilometres, and contains about half as much sand as the Sahara, despite being only around 1/15th of its size (this is due to the fact that the Sahara is largely made up of rocks and gravel). Summer temperatures in the Rub’ al-Khali can peak at more than 55°C in the shade, and the little rain that does reach the desert tends to fall erratically, meaning that some areas can go for several years without any precipitation.

Above Rub Al Khali

Wind blowing from multiple directions has created these star dunes at Ramlat Fasad on the Yemen–Oman border. Unlike other dunes, star dunes grow upwards rather than sideways, and consequently can grow to be some of the highest in the world.

Above Rub Al Khali

Star dunes spread out like fingers in the remote Omani part of the Rub’ al-Khali near Wadi Mitan. Although sand is the predominant feature of the Rub’ al-Khali, the desertscapes range from fine, soft sand and altitudes of up to 610 metres in the west to the east’s salt-encrusted mud flats, which are notoriously difficult to drive across. Star dunes tend to occur on the edges of sand seas, and in the Rub’ al-Khali are largely found in the east and south of the desert, where they can grow to a height of 200 metres.

Above Rub Al Khali

Chains of static star dunes form ridges tens of kilometres long, parallel to the predominant wind direction, in the Uruq al Mutaridah, Saudi Arabia. The Rub’ al-Khali is believed to have formed around two million years ago, its sands originally ground down from volcanic highlands and dry seabeds. However, more recently (from around 37,000 to 17,000 years ago, and from 10,000 to 5,000 years ago) small lakes formed on its surface following heavy rains, and fossils show that these temporarily hosted animals such as hippopotamuses and water buffalo. Although the landscape today appears to be devoid of life, numerous well-adapted plants and animals can be found throughout the region. Among them is the oryx, a type of antelope that can survive for several months by licking up the morning dew it finds on plants when free water is unavailable.

Above Rub Al Khali

Star dunes in Ramlat Fasad on the Yemen–Oman border. Although there are no permanent settlements in the centre of the Rub’ al-Khali, Bedouin tribes have lived around its edges for thousands of years, historically trading camels and frankincense. The desert remained largely unexplored by Europeans until the 20th century, when Englishman Bertram Thomas completed the first crossing in 1931.


An unusual collection of dot-shaped dunes spreads across the plain of Wadi Hazar in the Yemeni part of the Rub’ al-Khali. It appears that a change in wind direction has blown the crescent tails from a field of so-called barchan dunes. Barchans are crescent-shaped dunes formed on relatively hard desert floors where there is a limited supply of sand and a strong prevailing wind. They can grow to a metre in height within just a few hours and move up to 100 metres per year, with smaller dunes often catching up to and overtaking larger ones.

Above Rub Al Khali

Dressed in black cloaks (abayas) and straw sun hats (nakhls), local women harvest wheat in Yemen’s Hadramawt Valley, where a series of spring-fed agricultural towns are bordered by 300-metre-high red cliffs. The valley was historically on one of the frankincense routes used to transport the perfumed resin to the coast. It was dotted with walled cities made of mud, including Shibam, which is now a UNESCO World Heritage site and contains numerous mud ‘skyscrapers’. For centuries, farming and frankincense trading were the predominant industries in and around the Rub’ al-Khali, but in 1948, the Al-Ghawar, one of the world’s largest oil fields, was discovered in Saudi Arabia, altering the traditional lifestyles of many of the people living on the desert’s fringes.

Above Rub Al Khali

A vertical view of a herd of camels crossing the sandy gravels of the Empty Quarter on their way to graze near Wadi Mitan in western Oman. Many of the females having bra-like coverings over their udders to keep their young from nursing until they have returned to camp for milking.

Above Rub Al Khali

A field being drip irrigated at Liwa, in the UAE. The aquifers in Liwa, used to water date crops, are rapidly drying up, and areas that once had water three metres underground now require wells more than 75 metres deep, while elsewhere, huge sinkholes have appeared.

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• Geographic location: Pacific Ocean
• Latitude/Longitude: 0°37’09”S, 90°21’29”W
• Population: 25,124 (2010)
• Ethnicity breakdown: 81% Mestizo, 7.5% Native Indian, 7.3% Caucasian, 4.2% African-Ecuadorian(2010)
• Land area: 3,093 sq miles (8,010 sq km)
• Ocean area: 23,000 sq miles (59,500 sq km)
• Number of islands: 127 (including 19 large, four inhabited)
• Language: Spanish
• Currency: US dollar

Aside from the Galápagos’ most famous residents – the giant tortoises – the islands are also home to the world’s only marine iguanas. They can be primarily seen lazing around in the sun sneezing excess salt everywhere, or occasionally diving into the water – they are excellent swimmers – in search of a meal, nibbling marine algae off submerged rocks. The islands are also home to land iguanas, including a bright pink species classified for the first time in 2009, after being located in a remote part of Wolf Volcano. Sharing the rocky coastlines with the marine iguanas are Galápagos penguins, the only penguin that lives at or near the equator. The roughly 2,000-strong bird population is mainly located in the colder, nutrient-rich waters of Fernandina and Isabela, and this small population size and restricted range means they are graded as ‘endangered’ by the IUCN. Further out to sea, the islands are also a hub of utmost importance for over 2,900 marine species, including sea lions and turtles. To the far north, the remote uninhabited Wolf and Darwin islands witness vast gatherings of hammerheads and even whale sharks, whose presence helped establish the Galápagos Marine Reserve in 1986, now – at 133,000 square km – one of the largest such reserves in the world.

1535 Discovered by Spanish
1832 Annexed by Ecuador
1835 Visited by a young Charles Darwin
1859 Darwin publishes his theory of evolution by natural selection, based on observation in Galápagos
1941 Used as a base by the US military for the duration of WWII
1959 Official creation of the Galápagos National Park
1978 Designated the world’s first UNESCO World Heritage Site
1986 Creation of the Galápagos marine reserve
2012 Death of Lonesome George

In 1941, the Galápagos’ human population consisted of just 810 people. The number of residents sky-rocketed during the 20th century, reaching 18,640 by 2001, and 25,124 by 2010. Population pressure meant that the islands were added to UNESCO’s ‘in danger’ list in 2007, promoting then-Ecuadorian President Rafael Correa to make reforms to the country’s ‘Special Law for the Galápagos’, essentially creating a separate citizenship for Galápagos residents. Its purpose was to act as a control on the number of mainlanders moving to what has become the richest province of the country (thanks to tourism) and threatening the sustainability of the biodiversity which made it such a profitable international tourist destination. Only authorised Galápagos residents are now allowed to work on the islands. Recognising these efforts, UNESCO subsequently reversed their decision in 2010.

The islands famously occur at the meeting point for three major tectonic plates, the Nazca, Cocos and Pacific. Tectonic activity is ongoing among the youngest, most western islands, such as Fernandina and Isabela, which are less than a million-years-old. Further east, where continental drift has carried them away from the volcanic hotspots which cause the islands to emerge from the sea in the first place, the oldest islands, such as Española and San Cristóbal, are between three and five million-years-old, and are still only just beginning the long process of erosion.
Each of the major islands consists primarily of one main cone-shaped volcano, with the exception of Isabela which is formed of six that have since merged together. Many of the islands have enormous underground tunnels formed by the cooling outer crusts of lava, with fast-flowing liquid inside. These were often used as habitats by native species for years, with the skeletons of extinct animals such as giant rats found inside.

The islands are home to between 552 and 614 known native plant species, more than 30 per cent of which are endemic. The flora of the Galápagos is predominately desert vegetation, given how only the humid highlands generally receive enough rainfall to sustain lush green plant life. The more common dry areas of the islands are frequently populated by shrubs and cacti, plants which are well-adapted to drought-like conditions, only flowering during rare periods of high rainfall. By the coasts, mangroves play a very important role in the local ecosystem, providing breeding sites for birds such as pelicans and frigate birds, as well as a shady refuge for marine wildlife.
Across the Galápagos, there are hundreds of threats posed by invasive plant species. There are at least 866 recognised introduced species now settled in the wild, the majority brought deliberately by humans. One of the most urgent threats is quinine, a tall, rapidly-growing evergreen tree introduced in the 1940s which has spread across Santa Cruz, significantly altering the ecological composition of the vegetation and making survival more difficult for native species. Similarly, the spiny Asian blackberry shrub, introduced in the 1970s, has been observed invading wetter parts of the archipelago and forming impenetrable thick forests, negatively affecting the seed germination of native species.


Oman AK


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