This puppet museum has one of the best collections of wayang (flat wooden puppets) in Java and its dusty cabinets are full of a multitude of characters from across Indonesia, as well as China, Vietnam, India, Cambodia and Europe. The building itself dates from 1912. Watch for free wayang performances on Sunday (10am to 2pm), which are very popular and crowded. There are also often more elaborate performances on weekends which can be very worthwhile.
Freelance guides can enhance your visit as many displays lack information and context. However, carefully agree to a price in advance and watch out for guides who may try to pressure you into making a puppet purchase at an exorbitant price.