Market houses are a notable feature of several Northern Ireland towns. While these market houses vary in styles of architecture, size and ornamentation, many were designed with three, four or even five bays on the ground floor which were an open arcade. An upper floor was often used as a court house or ballroom. Ornamentation consisted of a cupola, a clock or sometimes a dome or tower. Today most of the market houses in Ireland have been put to use as cultural venues or business premises. Some are still derelict.