The Forgách Castle is located in Szécsény, in the central part of the town, on the Castle Square.

The castle, the predecessor of the present building, was built by Tamás Szécsényi or his sons from the second third of the 14th century. However, the Turkish wars caused great damage to the building. István Koháry had the outer walls of the castle and the castle buildings renovated continuously from 1690. János Forgách, the chief bailiff of Nógrád, and his wife Margit Cziráky recovered most of the manor from the Koháry's lien until 1739. In 1753, János Forgách's younger son Zsigmond inherited the estate. The Baroque reconstruction of the Szécsény castle between 1750 and 1760 is thus most probably attributable to Zsigmond. After Zsigmond Forgách, his second son József inherited the estate, and was responsible for the creation of the large English park. The Pulszky family owned the castle in the second half of the 19th century, except for the period 1849-1867, when it belonged to the Imperial Treasury. It was bought by the Budapest lawyer Jenő Gross in 1900 and sold to Baron Béla Lipthay in 1943. The building was badly damaged by the war and renovation began in the 1960s. The most recent renovation took place in the summer of 2005.

The Ferenc Kubinyi Kubinyi Museum in Szécsény has been housed in the renovated Forgách Castle since 1973. On 1 February 1979, the museum officially took over the name of Ferenc Kubinyi, the first archaeological researcher in the county, as a tribute to the renowned scientist. It has an archaeological and historical collection as a regional museum.