The New Town was envisaged as a mainly residential suburb with a number of professional offices of domestic layout. It had few planned retail ground floors, however it did not take long for the commercial potential of the site to be realised. Shops were soon opened on Princes Street, and during the 19th century the majority of the townhouses on that street were replaced with larger commercial buildings. Occasional piecemeal redevelopment continues to this day, though most of Queen Street and Thistle Street, and large sections of George Street, Hanover, Frederick and Castle Streets, are still lined with their original late 18th century buildings.