Stadtbefestigung Friesach, Medieval defense system in Friesach, Austria.

Stadtbefestigung Friesach is a medieval defense system in this Austrian town featuring a main wall reaching eleven meters high, a lower outer wall, and a fifteen-meter-wide moat. The structure also includes three surviving defensive towers from the 14th century that visitors can see today.

The original ring wall was built around 1200 but proved insufficient for defense, resulting in three conquests of Friesach between 1275 and 1292. The fortifications were then reinforced with additional walls and towers to better protect the city.

The moat survives because locals fought to keep it: a citizens' association founded in 1985 raised money through events and the campaign "Rettet den Stadtgraben" (Save the Moat). Falling groundwater and the town sewer had lowered the water level, and without winter ice the walls cracked in the 1980s, with whole sections collapsing.

The fortification path is accessible and allows visitors to examine the three surviving towers up close. Comfortable shoes are recommended, and care should be taken when exploring the walls and structures.

The moat is fed by groundwater springs and once drained into the town sewers; today its outflow lies at the southern end of the ditch. When the water table dropped and winter ice stopped forming, whole sections of wall collapsed in the 1980s, prompting the founding of the Stadtgrabenverein in 1985.