Time Out says
Taking place sporadically over 11 nights in August, Witches’ walk is an interactive tour of Zagreb's upper town. It's particularly good and is presented by three or four local 'witches’. Walking through the streets you'll meet various costumed characters, find out how they lived and what they did. A fun and informative presentation. Ticket price is 130kn per person, for children younger than 12 years, the price is 100kn. Check their website for tour info and bookings.