Where does the story Number the Stars take place?

Number the Stars is a historical novel written by author Lois Lowry that tells a critically important story about Nazi occupation during World War II and about the heroic, admirable actions of people who sought to protect the Jews from persecution. The story mostly takes place in German-occupied Denmark in 1943, and the city of Copenhagen is at the center of many of the events in the novel.
The entire novel only consists of seventeen short chapters, but it is densely packed with suspense. It tells the story of Danish families that successfully helped many of their fellow Jewish citizens escape Denmark during Nazi rule and avoid death and suffering. The characters are able to escape to Sweden, so some of the events also take place there.
The question does not ask about a synopsis of the story, but, just to offer some specific background information, I would like to add that the Johansens, a non-Jewish family, protected and assisted the Rosens and some of their other Jewish friends. They were part of the Danish Resistance, which proved to be a heroic, compassionate, and inspiring effort during the wartime persecution. This is why the events take place mostly in Denmark.