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This 1902 mansion with myriad classical influences was the summer home of novelist Edith Wharton. The 42-room house and 3 acres of formal gardens were designed by Wharton, who is considered by many to have set the standard for 20th-century interior decoration. In designing The Mount, she followed the principles set forth in her book The Decoration of Houses (1897), creating a calm and well-ordered home. Nearly $15 million has been spent to date on an ongoing restoration project that recently restored the third-floor bedroom suite. Summer programs includes free concerts on the terrace. Take one of the guided tours, or schedule a private "ghost tour" after hours.