Another quiet place is the Suedfriedhof - an old cemetery close to the center only a 15-minute walk from Marienplatz or 2 minutes from Sendlinger Tor. Here you will find Munich's celebreties of the 18th and 19th centuries, e.g. painters (Spitzweg), architects (Klenze) and scientists (Fraunhofer). I crossed the cemetery each time I had to walk downtown for shopping.
'Suedfriedhof' - a cemetary at the Kapuzinerstr. Many famous peoploe who have lived and died in Munich (Spitzweg, Thiersch, Liebig, etc...) are buried there. It has a very nice atmosphere in autumn and winter. In terms of german cemetaries it is quite unusual.