Set in the exquisite Nickerson Mansion, the Driehaus Museum immerses visitors in Gilded Age decorative arts and architecture. You'll feel like a Great Gatsby character as you wander the three floors stuffed with sumptuous objets and stained glass. Guided tours ($5 extra) are available at 11am and 2pm (1:30pm and 3pm on Sundays). No need to book; just show up 15 minutes beforehand.