Semi circular arches have been around for centuries.

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They were first introduced to England when the Normans came in 1066 with many churches bearing witness to this as porch entrances and north doors show the detailed and decorative stonework. Only a few windows remain with semi circular heads as this were replaced with the later Gothic styles of window. The actual construction of the arch has not altered, the same principles of a timber arch centre being used to support the bricks/stones as it is built has continued throughout the centuries.