XYZ Line
The XYZ Line (Spanish: Línea XYZ), also known as the Matallana Line, was a system of fortifications built in 1938 during the Spanish Civil War to defend Valencia, the capital of the Second Spanish Republic. The XYZ Line was a simple system of trenches and bunkers, built to withstand heavy artillery or 450-kilogram (992 lb) aerial bombs, and took advantage of some of the most difficult terrain in Spain in the Iberian System ranges to the north and northeast of Valencia.