Forget the theme park rides. Impress the kids with a half-mile rumble deep into the pitch-dark earth for tales of iron ore at Soudan Underground Mine State Park. Have a science geek in the family? Wow them by descending into the University of Minnesota’s subterranean High Energy Physics Lab for a tour. 1379 Stuntz Bay Rd., Soudan; 1-218-753-2245; mndnr.gov