In 1336 "the town was deserted and destroyed by the instability, death and heavy burdens on its neighbours."

At about the same time the present layout of the old town was created, consisting of a nearly six blocks, though its straight streets are reminiscent of a Roman camp.

Santa Cilia became a municipality in 1834 and attained its greatest population in 1920 with 520 inhabitants and about 90 houses.

However emigration, mainly to Argentina, France and Barcelona reduced its size to the present day level.

Population data for Santa Cilia between 1842 and 2007:[4] Its airfield is a popular with glider pilots who wish to explore the nearby Pyrenees.