The Skansen is an open air museum but one that won't scare you: over 150 relocated historic buildings from all over Sweden. Those open are attended by informative people in costume of the period of the house. Bears and other wild animals will captivate the children. Allow a whole day. 50Kr per person, children free but there is a 20 Kr discount with the travel card. Times vary: to end of April: 10.00-16.00; May: 10.00-20.00; June- Aug: 10.00-22.00.
Nearby is the Nordiska Museet of Swedish history and life: again don't be put off by the name and content. (free).
Moderna Museet and Arkitektmuseet are free and on Skeppsholmen: great collections (especially the models in the architecture museum) all in Rafael Moneo's building. T/W: 10.00-20.00; Thur-Sun: 10.00-18.00
Skansen located on Djurgårdsslätten, use bus 47, 44 or better the tram line 7 (try the café tram).
Aside from the normal try: the Stadsbiblioteket (national library) on Odengaten. Designed by Gunnar Asplund in 1924-8 a stunning series of spaces lovingly used and preserved. The same architect designed the Southern Cemetery (Skogskyrkogården with metro stop of same name): the chapels are in use so access is difficult although the landscaped grounds are beautiful and reflective.
Asplund worked with Sigurd Lewerentz on the cemetery: the latter designed one his two great churches in southern Stockholm: Markuskyrkan at Bjorkhagen (1958-60): one of the great post war buildings.
If you liked the dark brick modernist space of Markuskyrkan then try Celsing's St Tomas kyrka at Vällingby (1951). Both these churches are right by the suburban metro stops.
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