Over the past year, members of the Somali Islamist militant group al Shabaab have fled southern Somalia, the geographic focus of its conflict with the new Mogadishu-based government. With support from an unmanned aerial vehicle campaign, Western-backed African Union forces have been expanding their control of the region and are slowly encroaching on remaining al Shabaab positions. As a result, a number of al Shabaab fighters have headed north to mountainous redoubts in the . Most of the al Shabaab fighters in Puntland have sought refuge in the Al Madow Mountains -- a verdant range sometimes known as the Galgala Hills or the Golis Mountains. Located in the coastal Sanaag region, the mountains are part of the larger Karkaar mountain range, which stretches from easternmost Puntland to just west of the Ethiopian border. The Al Madow mountain range's primary ridgeline runs more than 200 kilometers (roughly 125 miles) parallel to the Gulf of Aden. The area has a more hospitable climate than most Somali regions and features thick forests -- especially on the range's steeper northern slope, which receives considerable precipitation from weather systems moving south off the gulf. The rough topography of the Al Madow range complicates efforts to observe and target militants -- a feature similarly enjoyed by militants hiding in northern Mali's Tigharghar Mountains. Unlike the Malian terrain, however, the thick vegetation of the Al Madow range further conceals militant activities and, where dense enough, can degrade the effectiveness of infrared detectors on unmanned aerial vehicles and other aircraft. The heaviest vegetation can obscure fighters from observation almost completely -- especially during the daytime, when human temperatures differ from the surrounding air less than at night. The mountains are also ideal due to the limited network of roads in the area, which effectively hinders and funnels the ground movements of attacking forces. This vegetation and rugged terrain have made the mountains of Puntland highly useful for various militias throughout history. Combined with tensions among regional clans and governments, access to local ports and smuggling routes, and a lack of African Union operations in the area, the mountains have made an ideal al Shabaab hideout as well, now and for the foreseeable future.