Kremnica Castle is a whole complex of buildings from the 14th-15th century that are protected by a double fortification. There's also a neo-gothic church of St. Katherine, a tower from which there's a nice view, an ossuary and other buildings belonging to the complex.
June - Sep:
Open daily except Monday: 8:30 am - 12:00 am, 1:00 pm - 5:30 pm
Oct - May:
Tue - Sat: 9:00 am - 12:00 am, 1:00 pm - 4:30 pm
Adult: €3
Reduced: €1.50
Wikipedia https://cs.wikipedia.org/wiki/Městský_hrad_v_Kremnici
Official Website http://www.muzeumkremnica.sk/en/the-town-castle
Address 568/1 Zámocké námestie, Kremnica 96701, Slovakia
Coordinates 48°42'22.266" N 18°55'3.359" E