Maritime boundaries are established through international bilateral or multilateral agreements and conventions. This screenshot depicts such boundaries for a part of the Channel and North Seas. EUROSION database does not just provide the geographical boundaries but also a link to the internationa convention which establishes these boundaries (by clicking on the relevant segment).

Data description

Maritime boundaries are established through international conventions. These conventions list the coordinates of points which are the vertices of segments which, in turn, define the maritime boundaries. This layer therefore features the following elements:

  • the textual content of international conventions establishing maritime boundaries in Europe. Maritime boundaries featured in this layer include territorial waters, bi- or multi-lateral boundaries (e.g. in the North Sea) as well as contiguous and exclusive economic zones. Some fishing areas are also defined.
  • The coordinates of points listed in these conventions are vertices of maritime boundaries
  • The maritime boundaries themselves, defined as the segments which links the different points listed in the international conventions.

Source of data

The main source of data comes out of the United Nations Convention on the Law of the Sea (UNCLOS), where nations define and update their sovereign claims to the ocean. Information provided by UNCLOS has been geocoded by EUROSION.


Restrictions are those cases where no regulatory text exists within the UNCLOS till now.

Quality This layer is entirely generated from the EUROSION project. Comparisons are being made with extracts of the copyrighted Global Maritime Boundaries Database (GMBD) distributed by the US based company Veridian. EUROSION targets a comparable accuracy as Veridian, but will remain copyright-free.
Copyright and data access conditions The layer “Maritime boundaries” of EUROSION database will be available without any restriction, since source documents are publicly accessible and for free at URL: http://www.un.org/Depts/los/LEGISLATIONANDTREATIES/europe.htm.