What is a broadly rectangular quarried stone used in paving roads called?
A Sett, also known as a block, Belgian block or Sampietrini, is a broadly rectangular quarried stone used in paving roads and walkways.
Formerly in widespread use, particularly on steeper streets because setts provided horses' hooves with better grip than a smooth surface, they are now encountered rather as decorative stone paving in landscape architecture.
Setts are often referred to as "cobbles", although a sett is distinct from a cobblestone in that it is quarried or worked to a regular shape, whereas the latter is generally a small, naturally-rounded rock. Setts are usually made of granite.
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