Centrum (central Copenhagen, aka downtown and city center) is packed with shops, restaurants, and businesses, as well as the crowning architectural achievements of Christian IV. Its boundaries roughly match the fortified borders under his reign (1588–1648), when the city was surrounded by fortified walls and moats.
Centrum is cut by the city's pedestrian spine, called Strøget (pronounced stroy-et), Europe's longest pedestrian shopping street (about 2 km [1 mile]). It's actually a series of five streets: Frederiksberggade, Nygade, Vimmelskaftet, Amagertorv, and Østergade. By mid-morning, particularly on Saturday, it's congested with people, baby strollers, and motionless-until-paid mimes. To the north of Strøget, you will find smaller, more peaceful shopping streets.