Maria Saal (Slovene: Gospa Sveta) is a market town in the district of Klagenfurt-Land in the Austrian state of Carinthia.

When pagan Slavic tribes entered the region around 590, they settled in a place called Krnski Grad (German: Karnburg), close to Virunum, which became the administrative centre of their Carantania principality.

After Charlemagne had finally deposed the Bavarian duke Tassilo III in 787, Karnburg remained the political capital when Carantania became a march of the Frankish realm.

When Emperor Emperor Otto II deposed Duke Henry II the Quarrelsome and finally separated Carinthia from Bavaria in 976, Karnburg also was the political centre of the duchy, a function that later was taken over by the ducal town of Sankt Veit an der Glan, a few miles to the north, and finally in the 16th century by the City of Klagenfurt to the south.

The present fortified church building goes back to the mid-15th century and is in high Gothic style, actually reconstructed within 20 years after the big fire of 1669.