The dataset contains the extent of the land claim (permanent or temporary establishments of the sea) and the type of construction reported by the Contracting Parties for the period 2016- 2021. The data was made available by HELCOM Contracting Parties in response to a data call. The data was reported by Denmark, Estonia, Finland, Poland, Russia, and Sweden. The activity was declared as not relevant in Germany and Latvia. Attribute specification and units (for points and polygons): Name: Name of the site Descrip: Brief description of the type of land claim Year: Year of construction, especially if built between 2016-2021 Area: Area in km2 Notes: Notes regarding the data Attribute specification and units (for lines): Country: Contracting Party that reported the information Type: Brief description of the type of land claim Estimated: Estimated year Area: Area in km2 Name: Name of the site descripto: Description of the site in national language Notes: Notes regarding the data