Many Norfolk wherries (trading ships) were built here. The leeboards are a distinguishing feature of wherries and Thames barges. Large sailing wherries employed a quant pole at least in length. On the southern Broads, steam wherries were used. A special wherry wheelbarrow was used to unload cargo, e.g. stone, from the wherries. Images of wherries can be seen on many pub signs and village signs. London passenger wherries evolved into the Thames skiff, a gentleman's rowing boat. Wherries came in different sizes, according to the river they used. Wherries were sail and oar craft dating back to at least 1604.