The garden city or garden suburb was a response to the social and environmental ills of cities at the turn of the twentieth century. Letchworth Garden City, Hampstead Garden Suburb, and Welwyn Garden City were built outside London in the early 1900s, and each remains a highly desirable place of residence today. From the start, each was tightly regulated, and remains so a century later. By protecting the appearance and enhancing property values, the strict application of historic preservation principles contribute to the long-term sustainability of each place. Similar garden suburbs were built in the borough of Queens in New York City in the 1910s and 1920s – Forest Hills Gardens, Jackson Heights, and Sunnyside Gardens. They also demonstrate the benefits of strict regulation, either by a self-governing association or under New York City’s Landmarks Preservation Commission.