The Town Fortification can be visited
Sankt Veit an der Glan Town Fortification

The city fortification of Sankt Veit an der Glan encloses the historic city.
History+
The city fortification was first documented in 1228. Its current form was mainly established in the 15th century. Due to the advancement of weapon technology in the 16th century, the fortifications were extensively reinforced, with a seven-meter-wide Zwinger (outer bailey) and shell towers being added. A heavily renewed bastion tower on the northwest corner, marked with the year 1532 on a stone, shows these alterations. The Herzogsburg was also integrated into the fortification. The original four gate towers were demolished between 1851 and 1890; today's gates are 20th-century additions.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://www.wehrbauten.at/ktn/kaernten.html
This description draws on the facts documented in the linked Wikipedia article; Wikipedia content is licensed under CC BY-SA 4.0. Wording and editing: Mobile History.
Location: 46.7672, 14.3557