Today, nothing can be seen from the former castle of Egerszeg. Only the county hall and prison in its place built between the 18th and the 20th century, and the street system preserve its memory in the center of Zalaegerszeg. However, during the archeological excavations in the area, the trail of the walls of the former wood/earth castle, consisting of pile wood holes, came to light on various sections. The virtual reconstruction of the 17th century castle was carried out with the help of archaeologists László Vándor and Zoltán Orha, based on the results of decades of archaeological research. Using the inventories and representations of the 19th century, we made it based on the architectural models of Gergely Buzás. We used the expertise of József Kelenik to authenticate the fortification. Of the few depictions of his time, the most detailed image was created by the Austrian military engineer Johann Le Dentu, it depicts the castle in the middle of the 17th century – in addition to archaeological data and written sources, this depiction formed the basis of the theoretical reconstruction shown here. Additionally the site plan of military engineer Jakob Holst from 1665 was processed also, and we can say that we used all the contemporary representations of Egerszeg for the work. It was an honor to work with Zalaegerszeg and the Göcsej Museum, thank you all for the joint creative work!