Cooper Hewitt, Smithsonian Design Museum

This guide to the Cooper Hewitt in New York opens with Andrew Carnegie's plan for the plainest, roomiest house in the city, built in 1898 on a stretch of Fifth Avenue so far uptown that locals called it goatville. It follows the mansion's sixty-four rooms and its unusual amenities, and the wealthy neighbors who followed Carnegie north and gave the area its name. Pick up the interactive pen at the door before you start through the galleries.