If you follow the street, Fisketorv, it will lead to Gammel Torv, which, for many decades, was the thriving main square of town and a meeting place of locals. It's said that Queen Margrethe I crowned her 6-year-old son, Oluf, on this spot.
Slagelse possesses two historic churches and a minor museum, but, frankly, most sightseers use the town merely as a base for exploring the Viking reconstruction at Trelleborg. If you're covering both Slagelse and Næstved in 1 day, you might skip the attractions in the center of Slagelse if you're pressed for time.
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