A Crinkle-Crankle wall, England.
The crinkle crankle wall economizes on bricks, despite its sinuous configuration, because it can be made just one brick thin. If a wall this thin were to be made in a straight line, without buttresses, it would easily topple over. The alternate convex and concave curves in the wall provide stability and help it to resist lateral forces.
Both crinkle and crankle are defined as something with bends and turns (Webster’s), but the term is also thought to come from Old English meaning zig-zag.
Many crinkle-crankle walls are found in the Fen Country of East Anglia.