South Holland (Dutch: Zuid-Holland) is a province of the Netherlands, located in the west of the country on the North Sea coast. It is the most densely populated and industrialised of the Dutch provinces.It contains the major cities of The Hague (Den Haag or 's-Gravenhage) (the seat of government of the country and the seat of the International Court of Justice) and Rotterdam. Dordrecht, Leiden, Delft, Gouda And Gorinchem have town centers with many 17th-century buildings.Rotterdam has one of the world's largest harbours. The province South Holland was formed in 1840, when the province Holland was split into northern (North Holland) and southern parts.