Large natural arches are somewhat rare outside the southern and western regions of China and the Colorado Plateau of the southwest United States.

[1] Chad's Ennedi Plateau, located within the Sahara Desert in the northeast part of the country near Libya and Sudan has a geology similar to the Colorado Plateau and has produced a number of natural arches and similar landforms, although only Aloba can claim to be on the top ten list of longest arches in the world.

[1] Due in part to its location as well as being only recently recognized for its size, estimates based on photography yield an approximate span of 250 ft (76.2 m).

[2] Xianren Bridge (Fairy Bridge) in China has a span of 400 ft (121.9 m) which is the longest discovered and measured span to date.

At 394 ft (120.1 m) tall, it towers over the more famous Rainbow Bridge and is one of the tallest known arches in the world.