Located in the eastern corner of northern Mali along the border with Algeria, the Tigharghar Mountains consist of a rugged wilderness that both grants protection and allows penetration of the border, across which the mountain chain extends into Algeria's Hoggar Mountains and Niger's Air Mountains. The area covers roughly 22,000 square kilometers (8,500 square miles), which is almost the same as the surface area of New Jersey. Within Mali, the Tigharghar chain is bordered to the south and west by stretches of desert that disconnect this region of the country from the nearest relatively populated area along the Niger River. Hunted militants in this flat, open terrain are much more vulnerable than they are in the mountains, although the sheer size of the desert territory makes them hard to locate.
The mountains' isolation from the population centers of Mali — as well as those in Algeria and Niger — complicates government control of the area. Because of its location outside the immediate reach of security forces and the interdicting nature of the terrain, the Tigharghar Mountains are a favorable location for staging a defensive guerrilla-style conflict or conducting illicit trade.
The mountains of the Tigharghar range are not particularly high, with the highest point — just along the Algerian border — reaching an altitude of only 700 meters above sea level. The real challenges in this area are the steep, craggy hills and valleys. The rough topography is strewn with riverbeds, or wadis, that are dry most of the year but still cut through the landscape. This broken terrain favors an established defender by making movement physically harder for personnel and mechanically restrictive on vehicles. It makes navigation difficult and limits line of sight, which is critical for employing any weapon system, including third-party platforms used for observation, such as unmanned aerial vehicles. This terrain also funnels movement, making travel routes more predictable and allowing those who understand the terrain to set up more effective ambushes.
The soil changes frequently between rocky and sandy terrain, making even the more easily navigable areas difficult to traverse with vehicles or on foot. This has encouraged the use of alternative means of transportation, such as camels and motorcycles. A limited, unpaved road network that connects towns with each other and Algeria facilitates mobility in the area. The towns of Kidal and Tessalit have paved runways that allow air traffic in and out of the region.
Trade and Smuggling in the MountainsThe Tigharghar Mountains are inhabited by a number of Tuareg tribes named Kel Adagh (in the local language, this means "those from the mountains"). Approximately 60,000 people are spread across towns and small settlements throughout the mountain chain. The largest concentration of the local population lives in the town of Kidal, which has more than 26,000 inhabitants. The two other major towns of the area are Aguelhok and Tessalit.
Most of the mountain towns, including the largest three, are on the western edge of the Tigharghar. The road running through them, from Kidal through Tessalit into Algeria, is part of the main route used for transporting goods between Mali and Algeria. Tessalit functions as a type of border post due to its location on this route. On the eastern side of the mountains, the town of Tinzaouatene — a historic trade post and military border post during French colonialism — hosts similar activity but not at the same scale since it is not connected as well with Kidal and the rest of Mali.
This region's position on a traditional trade route has become useful in the world of illicit trade, including cigarette smuggling, drug trafficking and the illegal arms trade. The complexity of the terrain along the border makes it extremely difficult to shut down the illegal transport of goods in this area. While large mountains would limit mobility, the moderately mountainous terrain in the Tigharghar contains many small paths that facilitate the movement of small groups and obscure them from observation. For example, some of the drugs that typically enter West Africa from South America by sea are then transported over land into the Sahel region, where most of them pass through or near the Tigharghar mountains to be moved further through Niger's or Algeria's desert terrain into Libya. Militant organizations have taken advantage of the same safety the terrain gives illegal traders and have begun using the mountains to launch activities such as kidnapping for ransom.
The Mountains' Value to Militants
The Tigharghar Mountains' suitability for illicit activity is one of the main reasons it is a sanctuary for organizations such as al Qaeda in the Islamic Maghreb or the Movement for Unity and Jihad in West Africa. As part of their offensive in Mali, which faced threats of a foreign intervention long before foreign troops began arriving in January, these militants intended to use the Tigharghar Mountains as their last resort. They made the mountains' terrain even more impassable by using landmines and improvised explosive devices and digging tunnels. The militants could already use the extensive network of caves in the mountains, the entrances to which are extremely difficult to spot; in fact, the only way to confirm a cave's location is to observe militants entering and exiting the cave. While the militants controlled most of northern Mali, they increased their capacity to store supplies and avoid detection by bringing in labor and heavy equipment from Gao to build tunnels. The tunnels hold food, fuel and ammunition, and some are large enough for trucks to enter.
Outside the tunnels and natural caves, which grant concealment from observation and cover from airstrikes, the surface terrain is rugged enough to provide cover and concealment despite the lack of vegetation. The broken terrain limits the effectiveness of unmanned aerial vehicles or other aircraft used for observation because the natural elevations create a shadow effect. Operating such aircraft at a higher altitude can eliminate this effect but lowers resolution and increases the area observed at one time. Air assets are also restricted in their movement by the elevations. Helicopters need to adjust angles to get proper fields of fire and might have to remain stationary, making them more vulnerable targets. Fixed-wing aircraft have to make runs along specific paths in order for munitions to come in from the right angle to be most effective. Moreover, the shadows created by the broken terrain limit the effectiveness of munitions, even for direct-fire weapons.
The weather in the Tigharghar Mountains further complicates air operations. Most of Mali has a five-month rainy season, during which ground mobility is constrained. The area north of Kidal has considerably less rain, with a rainy season that lasts only through July and August. This makes the mountains more vulnerable to sand and dust storms, which can keep air assets downed, damage sensitive technological equipment, degrade vehicle performance and limit observation of the surface from the air. This type of adverse weather usually works in favor of combatants that know the terrain intimately.
The accumulation of these geographical conditions has made this area a desirable base for militant and illicit activity beyond the direct reach of security forces in the region. The nomadic cultures that have populated this area for centuries are based on this specific use of the terrain: Desert raiders survived there by attacking convoys carrying wealth or supplies or by reaching out across the desert to raid populated regions before retreating to the rugged terrain where they would not be threatened. In much the same way, militants are now trying to escape the flat deserts where foreign forces immediately have the advantage by withdrawing into the Tigharghar Mountains with the intent of establishing a stable base there that would allow them to survive the operations conducted against them. The constraints imposed by the terrain make fighting less efficient for attackers, even if they are better equipped, better trained and more numerous than the defenders.