Stonehenge

The great accuracy with which these massive blocks were handled seems to imply an outside influence, possibly connected with the Mediterranean; but the most remarkable feature, from an architectural point of view, is the use of optical corrections. Each of the central trilithons has been shaped to counter the effect of perspective when looked at from below. The uprights taper in a curve which has similar properties to that of a Greek column, and the lintels have a wedge-shaped section which gives visual strength to its span.