Cooper-Hewitt National Design Museum

This museum is in the 64-room mansion built by billionaire Andrew Carnegie in 1901 in what was, in those days, way uptown. Within 20 years, the bucolic surroundings that Carnegie craved disappeared as other wealthy men followed his lead and built palaces nearby. Carnegie was an interesting character: an avid reader and generous philanthropist, he dedicated many libraries around the country and donated some $350 million in his lifetime. To learn more, take the 45-minute guided tour (noon & 3pm Mon-Fri, 12:30pm & 2pm Sat & Sun), included in the admission price.

Part of the Smithsonian Institution in Washington, this house of culture is the only museum in the country that’s dedicated to both historic and contemporary design. It’s a must for anyone interested in architecture, engineering, jewelry or textiles. Exhibitions have examined everything from advertising campaigns to Viennese blown glass. Even if none of this grabs you, the mansion is stunning and the museum’s garden and terrace are well worth a visit.