Coastline has been publicly released on the HHI Geoportal, also allowing download services (WFS). For ease of use, the coastline is divided by counties.
The Adriatic Sea coastline is plotted on official nautical charts as the boundary between the land and the sea. Hydrographic Institute of the Republic of Croatia defines coastline as the intersection of a land surface and a geoid surface determined by the mean high water on the tide gauges at Koper, Rovinj, Bakar, Split, and Dubrovnik for the epoch 1971.5 (Domijan et al., 2005). This definition is in accordance with the decision of the International Hydrographic Organization (IHO) on the delineation of coastline.
The coastline is derived from fair charts of different scales, being further periodically aligned with the new hydrographic survey data and the State Geodetic Administration digital orthophoto.
The publicly released coastline can be used without restrictions, with mandatory indication of sources. 
Hydrographic Institute of the Republic of Croatia, as subject of the National Spatial Data Infrastructure (NSDI), has published the coastline metadata in the NSDI Metadata Catalogue.