Croatia is the only country bordering the adriatic sea that has exploration blocks and offshore production and does not allow any exploration nor production within ten kilometers of the mainland.
An exploration block is an area in which the permit/license holder is allowed to carry out exploration activities, under strictly controlled conditions, for the purpose of hydrocarbon exploration. As of April 2014, in the Croatian portion of the Adriatic Sea, 28 exploration blocks have been demarked. These blocks vary in size from approximately 1,000 to 1,600 km².
In accordance with Croatia's Act on the Exploration and Production of Hydrocarbons, the Government of the Republic of Croatia announced First Offshore Licensing Round for Licences for the Exploration and Production of Hydrocarbons on April 2nd 2014. One of the activities which preceded the public license round was demarcation of exploration blocks. To provide the utmost protection for the environment, tourism, fishing and other industries as well as to mitigate any potential effect of exploration leading global mitigation measures were applied when the blocks were demarcated.
For example, an exclusion zones of ten kilometers from the the mainland and an additional six kilometers from the islands were applied. It is important to note that prior to the new April 2014 block demarcation no exclusion zones existed. Meaning that with the previously existing blocks exploration was allowed in 100% of Croatian Adriatic waters, including waters next to coastal beaches as well as waters inbetween islands and the islands themself. For example, previously drilling activities occurred on the islands of Brač, Vis, Krk, Ugljan, Dugi otok, Silba and in the costal area of Istria.
Today, thanks to the new regulatory framework, drilling on the mentioned islands is no longer possible nor is drilling possible within ten kilometers of the mainland and six kilometers from the islands. In fact, Croatia is the only country bordering the Adriatic Sea that has exploration blocks and offshore production and does not allow any exploration nor production ten kilometers from the mainland.