The main attractions of the Primorsko-notranjska region include the underground karst with the world famous Postojnska jama cave and the intermittent Lake Cerknica. The region is also known for its rich heritage of military history. Due to its favourable geographical location and transport links with regional centres (Ljubljana, Koper, Trieste and Rijeka), more than a third of the working age population work in other regions. Despite its extensive forest cover, the region is facing the decline and collapse of its larger companies, especially in the wood processing industry.