Randers' main attraction is Randers Regnskov, the tropical zoo built inside glass domes over the Gudenå river — one of the more unexpected experiences in Jutland and worth a half-day. Beyond that, the town has a pleasant old quarter with Sankt Mortens Kirke, a significant medieval church where Denmark's Reformation effectively began; the Randers Museum of Art, which holds a solid Danish art collection; and the Kulturhuset, the main venue for concerts and events.
The oddest attraction is Memphis Mansion, a full-scale replica of Graceland on the edge of town built by a dedicated local Elvis fan. It is what it sounds like, executed with improbable commitment.
The Gudenå, Denmark's longest river, runs through town and is ideal for kayaking downstream toward Randers Fjord.