A sett, usually referred to in the plural and known in some places as a Belgian block, is a broadly rectangular quarried stone used for paving roads. 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 inaccurately referred to as "cobbles": 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.
Notable places paved with setts include many streets in Rome (Italy, since the technique was first used by Romans) in Aberdeen (Scotland), much of Edinburgh's Old Town and New Town, and Red Square in Moscow.
Silloth on Solway, the seaside town in Cumbria, still has the setts (originally laid in the 19th century) on Eden St and the seafront Criffel Street. Streets paved with setts feature in cycling competitions including the "Tour of Britain" which visited Silloth on Solway in 2015.
In Bruges, Belgium, most roads are in Belgian block in the center, but in the recent years, a lot of them have been replaced by asphalt to reduce noise.
In New York City, the West Village (including the Meatpacking District) and SoHo neighborhoods retain such streets. Older sections of Brooklyn such as DUMBO and surrounding neighborhoods also have streets baring Belgian blocks.