The castle was probably built in the first half of the fourteenth century, after the division of the Balog family property, which occurred in 1297 between the branches of the family from Blh, Rimavská Seč and Drienčany. Nicholas Balog, whose son Ladislav wrote from Drienčany, took part in it. Perhaps one of them was the founder of the new, modest castle Drienok. It did not appear in written documents until 1413. Its end can be associated with the beginning of the second half of the 15th century. At that time, post-Hussite troops of Jan Jiskra appeared at the time, with whom John Hunyady fought in Drienčany in 1452. Their final liquidation took place in 1460 during the campaign of Sebastian Rozgonyi, who captured Drienčany and probably also Drienok, who was probably destroyed at that time.
The castle had a shape similar in plan to a pentagon measuring 120 x 70 meters. In its south-eastern part there was an oval-shaped upper castle with two chamfered corners, measuring about 30 by 25 meters and wall thickness 1.85 meters. Within it was a residential building with two rooms on the ground floor level. It is not known if it was tower-like. The castle core was separated from the rest of the area in the east and north-east by an 18-meter wide and 4-meter deep ditch. A small four-sided building protruded towards the ditch, perhaps serving as a gate tower. The second building protruding from the perimeter was in a corner on the south-west side.
On the north-west side there was the mentioned extensive ward (120 x 70 meters). Its fortifications were of wood and earth structure, and from the north in the place where the outer bailey narrowed, it was protected by a 20-meter wide ditch. In addition, frontal fortifications were erected at a distance of about 55 meters in the further foreground of the castle. It had an oval shape (22 x 25 meters), protected from the west and south by a 18-meter-wide ditch with a depth of 4 meters. Even these fortifications were not enough for the castle owners, because on the hill 175 meters away one more fortifications (19 x 16 meters) were created, surrounded by two earth ramparts and a ditch with a total diameter of about 67-68 meters. These fortifications in the foreground belong to one of the largest in today’s Slovakia.
The castle has not survived to modern times. Only relics of foundations and earth fortifications are now visible. The whole is located on a heavily wooded area.
Bóna M., Plaček M., Encyklopedie slovenských hradů, Praha 2007.