What’s in a wall but a simple structure to keep intruders out, you might say. But a surprising amount of thought goes behind the construction of some. One example is the crinkle-crankle wall, popular in the county of Suffolk, in east England. The alternating curves of the crinkle-crankle wall prevents the wall from toppling over without the need for buttressing. Another unusual wall is the quirkily named “Ha-Ha” that’s found in many 18th century country estates around Britain.

Photo: Tim Dawson/Flickr