Old Castle's history begins in the 13th century with a basilica and a cemetery being built on its grounds. In the 15th century a fortress was erected to protect people from Turks. It truly is a "stone chronicle of Banska Stiavnica" and you can admire exhibitions of religious arts, history of miners and the whole castle as well.
It's also surprisingly vast and there are many hidden spots to wander into.
Please check the official website, the opening hours vary.
Without a guide:
Children 6-18, Studens, Seniors 62+: €2
With a guide:
Children 6-18, Students, Seniors 62+: €1.50
Official Website https://www.muzeumbs.sk/
Address 40/10 Starozámocká, Banská Štiavnica 96901, Slovakia
Coordinates 48°27'34.556" N 18°53'27.524" E