Cobble stone

Cobblestone is a natural building material based on cobble-sized stones, and is used for pavement roads, streets, and buildings.

In England, it was commonplace since ancient times for flat stones with a flat narrow edge to be set on edge to provide an even paved surface. This was known as a 'pitched' surface and was common all over Britain, as it did not require rounded pebbles. Pitched surfaces predate the use of regularly-sized granite setts by more than a thousand years. Such pitched paving is quite distinct from that formed from rounded stones, although both forms are commonly referred to as 'cobbled' surfaces. Most surviving genuinely old 'cobbled' areas are in reality pitched surfaces. A cobbled area is known as a "causey", "cassay" or "cassie" in Scots (probably from causeway).

Setts are often idiomatically referred to as "cobbles", although a sett is distinct from a cobblestone by being quarried or shaped to a regular form, whereas cobblestone is generally of a naturally occurring form.

Cobblestones are typically either set in sand or similar material, or are bound together with mortar. Paving with cobblestones allows a road to be heavily used all year long. It prevents the build-up of ruts often found in dirt roads. It has the additional advantage of not getting muddy in wet weather or dusty in dry weather. Shod horses are also able to get better traction on stone cobbles, pitches or setts than tarmac/asphalt. The fact that carriage wheels, horse hooves and even modern automobiles make a lot of noise when rolling over cobblestone paving might be thought a disadvantage, but it has the advantage of warning pedestrians of their approach. In England, the custom was to strew the cobbles outside the house of a sick or dying person with straw to dampen the sound.

Cobblestones set in sand have the environmental advantage of being permeable paving, and of moving rather than cracking with movements in the ground.

Cobblestones were largely replaced by quarried granite setts (also known as Belgian block) in the nineteenth century. The word cobblestone is often wrongly used to describe such treatment. Setts were relatively even and roughly rectangular stones that were laid in regular patterns. They gave a smoother ride for carts than cobbles, although in heavily used sections, such as in yards and the like, the usual practice was to replace the setts by parallel granite slabs set apart by the standard axle length of the time.

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