Roman defence system presented at National Museum

"Claustra Alpium Iuliarum - the Mysterious Legacy of Ancient Romans" will present the namesake late-Roman defence system running across the present-day Slovenia and Croatia that was abandoned in the 5th century.

The exhibition, which will be open until 18 February, features digital 3D reconstructions of the stone walls with defence towers, maps, illustrations and photographs of the remains.

It also includes a documentary on what was the biggest Roman architectural achievement on the Slovenian territory in the 4th century.

The remains of the defence system, which used all of the defence potential of the natural terrain, is one of the most important pieces of Slovenian cultural heritage, the museum said.

Sections of the fortification system blocked all roads leading towards Italia, acting as the final defence line that protected the rich and fertile plains of northern Italia from possible invasions from the East.

The Claustra consisted of a series of interconnected fortifications with its centre at Castra ad Fluvium Frigidum in the present-day Ajdovščina area. Other important fortresses were Ad Pirum on today's Hrušica Plateau and Tarsatica, now a part of the Croatian city of Rijeka. They had been governed from Aquileia in present-day Italy.

The system was about 130 kilometres long, featuring more than 30 kilometres of walls that were 1-2 metres thick, more than 100 defence towers and eight fortresses.

The exhibition, which first opened at the National Museum in August 2015 before travelling to Croatia, was set up as part of the Slovenian-Croatian project Claustra - Stone Defence of the Roman Empire.

As part of a follow-up project called Claustra+, the two countries will protect and promote this shared heritage and use it as a basis for developing cultural and green tourism.