Klis Fortress is a Medieval fort situated above a village bearing the same name, near Split Croatia. From its origin as a small stronghold built by Illyrian tribe Dalmatae, becoming a Royal Castle that was the seat of many Croatian kings, its finale development as a large fortress during the Ottoman wars in Europe, Klis Fortress has guarded the frontier being lost and re-conquered several times throughout its more than two-thousand-year-long history. Due to its location on a pass that as a major source of defence in Dalmatia, especially against the Ottoman advance, it has been a key crossroad between the Mediterranean belt and the Balkan rear.
Ancient stronghold as the Romans, the ancient tribe of Dalmatae which held a stronghold on this spot were the first known inhabitants who lived on the site of what is today Klis Fortress. They were defeated several times, and in year 9 AD, finally annexed by Romans. Today's Klis Fortress was known to the Romans by the name of Andetrium and in later times, Clausura which is the origin of later Clissa and modern Klis. To the Romans, Klis became famous for its celebrated siege by Augustus, at the time of the Illyrian revolt in Dalmatia. The road that leads from Klis to Salona was called Via Gabiniana or Via Gabinia which according to an inscription found at Salona, appears to have been made by Tiberius. Southeast of the Fortress, the traces of a Roman camp are still visible as well as an inscription carved on a rock. Both which are supposed to be contemporary with the siege under Tiberius. The description of this siege during Illyrian wars demonstrates that this place was strong and unreachable in those times. The Fortress is located above a village bearing the same name 11 kilometres (6.8 mi) from the Adriatic Sea on a pass that separates the mountains Mosor and Kozjak at the altitude of 360 meters (1,180 ft), northeast of Split in Croatia. Owing to its strategic position the Fortress is regarded as one of the region's most important fortifications. The Klis Fortress has been developed as a visitors attraction by the Kliski Uskoci re-enactment association in Klis with the aid of the Conservation Department of the Ministry of Culture in Split. Visitors to the historic military structure can see an array of arms, armour, and the strength of its people, traditional uniforms in buildings which were formerly an Austrian armoury. Klis is remembered in a Croatian byword based on the distance of Klis and the strength of its people: It is difficult for Klis because it is on rock and it is difficult for the rock because Klis is on it.