This town is the capital of midcentury mod style, and the Sunnylands Center & Gardens (pictured) is a mega-shrine to modernism. The former winter home of publisher and diplomat Walter Annenberg and his wife, Leonore, is an architectural vision, with the bonus of a powerhouse art collection, including works by Rodin and Giacometti. Garden and gallery free, house tour $35; sunnylands.org
Best time to go: June, for fewer crowds and killer deals—if you can take the heat.
Stay: The recently renovated Saguaro, complete with large pool and mountain vistas, adds a contemporary pop of color inspired by desert wildflowers. From $105;