If there's one feature of the Cotswold landscape that sums up its special flavor, it's the oolitic limestone that is the area's primary building material. This stone can be seen in everything from drystone walls (whose total length in the region is said to equal or exceed that of the Great Wall of China) to snug cottages and manor houses. Even roof tiles are fashioned from the stone, contributing to a harmonious ensemble despite the different ages of the buildings.
Malleable when first quarried, and gradually hardening with age, the stone lends itself to every use. During the late-medieval heyday of the great churches funded by wool merchants, it was used to brilliant effect in the mullions, gargoyles, and other intricate decorations on ecclesiastical buildings. Some area quarries are still active, producing stone that is used mainly for restoration and repair purposes. The varying colors of the stone are caused by impurities in the rock. They include the honey hues of the northern reaches of the Cotswolds, and modulate to a more golden tone in the central area, with a paler hue in and around Bath.
Writer and commentator J. B. Priestley, however, wrote of Cotswold stone that "the truth is that it has no color that can be described. Even when the sun is obscured and the light is cold, these walls are still faintly warm and luminous, as if they knew the trick of keeping the lost sunlight of centuries glimmering about them." Walk or drive around Cotswold villages and towns for even a day, and you will know what he meant.