National Museum of Poland
"National Museum of Poland" is the overarching name for several of the country's largest and most notable museums. Poland's National Museum comprises several independent branches, each operating a number of smaller museums.
The main branch is the National Museum in Kraków (Polish: Muzeum Narodowe w Krakowie), established in 1879. It has several hundred thousand items in its permanent collections, kept mostly at the Main Building on 3 Maja St., and partly in eight other divisions around the city.
Wikimedia Commons has media related to European painting in Poland by museum.