Castra ad Fluvium Frigidum

Castra ad Fluvium Frigidum is a Roman fortress measuring 220 meters long and 160 meters wide, built entirely from stone. The defensive walls stand approximately 3.4 meters thick and are reinforced by towers, several of which remain visible today.

The fortress was built around 270 AD as part of a larger Roman defensive system in the region. It served as a key military installation protecting this strategic frontier during the late Roman period.

The name refers to the nearby river, reflecting how the Romans tied this fortress to the waterway. Visitors can still see how the layout connects the fortifications directly to the water's edge.

Visitors can directly examine multiple preserved wall sections and the foundations of various structures on the site. The best time to visit is during stable weather when the grounds are drier and easier to explore.

The fortress was positioned at the confluence of two water sources, giving the Romans both a supply advantage and defensive control over traffic. This geographic placement made it a crucial checkpoint for monitoring the ancient trade route that passed through the area.

Location: Ajdovščina Municipality

Inception: 270

Height: 3.4 m

Length: 220 m

Width: 160 m

Made from material: stone

Part of: Claustra Alpium Iuliarum

GPS coordinates: 45.88822,13.90375

Latest update: December 14, 2025 09:44