Harbour is a subtheme of City that was introduced in 2011, and was discontinued in late 2012 though one of the sets considered part of the subtheme, 4645 Harbour, was released in 2007. The theme focuses on seaside and ocean sets. One port has been released, along with a beach marina area.
This theme's roots came when Transportation was released in 2007. It included a container ship and container stacker. After that, LEGO made new Harbour sets in 2011. These new sets are more civilian based than the previous version.
Please see Category:Harbour (City) sets