A syncline is a geological formation characterized by a downward-curving fold in rock layers. In a syncline, the youngest rock layers are typically found at the center, while older layers are located on the outer edges. This structure often forms as a result of tectonic forces that compress the Earth's crust. Synclines are commonly found in areas with significant geological activity, such as mountain ranges. They are often studied alongside their counterpart, anticlines, which are upward-curving folds. Understanding synclines helps geologists interpret the history of the Earth's surface and the processes that shape it.