One of the main attraction in Novogrudok are the ruins of ancient castle.
This castle (also named as Mindaugas's castle) was built on the site of ancient settlement on the Сastle hill - high, partly artificial hill, which was surrounded by a moat. Ancient legends tell that several hills were on the site of Novogrudok. The first settlements were located on them. However, at first people thought that this hill was cursed.The whole thing was that the first houses on this hill were burned by lightning. However, with the passage of time locals start live here.
Firstly here was only circular defensive rampart with wooden buildings. At the beginning of the XIII century was built a stone square tower, which was called the Shield or Central. It served as the main element of the defense of the stone castle which was built here. The castle with central tower was founded by the first Grand Duke of Lithuania Mindaugas. The tower survived the assaults of the Galician-Volyn, Tatar and other troops, and in the end of the XIV century it was rebuilt again, but from a brick.
In the late XIV - early XV centuries, preparing to defend the settlement against the Teutonic order of Knights in the Castle were erected three towers which were connected by walls. On the western slope of the Castle hill was built water well tower over the spring. This tower had a secret entrance to the Castle and a special passage to water. In this form castle resisted numerous attacks of the Crusaders. In the late XV - early XVI centuries because of raids of the Tatars the castle kept on strengthening. In the northwestern part was built Watch tower.  A new wall has connected it with the Shield Tower. At the same time on the southeastern slope was built tower-gate, which was connected by walls with Well tower and Small Brama.  As a result, there were two polygonal defensive belt, one on top and the other on the hillside. In the 16th century, the Castle consisted of seven towers and was one of the most powerful fortifications in Belarus.
During the Russo-Polish war in 1654-1667 the castle was badly damaged. Four towers was completely destroyed. The final blow to the castle walls was striked by the Swedes during the Great Northern War. At the beginning of the XX century there were only three towers on the top of the hill. During the XIX century first tower was dismantled. In 1906 second tower was collapsed. During the First World War south wall of the Shield Tower was destoyed. Only in 1921 the castle ruins was taken under protection. In 1922-1920 here was carried out a partial preservation of the surviving wals. Jousting festivals and tournaments are held on the territory of Novogrudok castle every year.