In case of bad weather in Munich, the best place you can visit is the Residence museum. The Munich Residenz (Münchner Residenz, Munich Palace) is the former royal palace of the Bavarian monarchs in the center of the city of Munich, Germany. The Residenz is the largest city palace in Germany and is today open to visitors for its architecture, room decorations, and royal collections. The complex of buildings contains ten courtyards and the museum displays 130 rooms.
You will visit the most important room in the end. The Hall of Antiquities (Antiquarium), built in 1568-1571 for antique collection of Albert V (1550–1579) by Wilhelm Egkl and Jacobo Strada, is the largest Renaissance hall to the north of the Alps.
At the official website, see opening hours and prices.
Getting there: Odeonsplatz metro station in Munich.