With the opening of the Royalton Hotel in 1988, Phillippe Starck ushered in the new age of boutique design hotels. But long before a front-desk-to-fourteenth-floor-faucets commission was de rigueur resume fodder for A-list designers, there were a handful of notable 20th century hotel designs by world-famous architects. The first to come to mind is likely Frank Lloyd Wright's sumptuous Imperial Hotel, a benchmark design from the middle phase of his epic career. The other is likely Arne Jacobsen's SAS Hotel in Copenhagen, the modernist 1960 design that spawned both the Egg and Swan chairs. But booking a room in these masterpieces isn't quite so simple. Visitors to Tokyo will be saddened to learn that although Wright's design survived both the Great Kanto earthquake of 1923 and World War II, it was demolished in 1968; meanwhile design geeks headed to Copenhagen will have to jockey for a stay in room 606, the single space in the SAS hotel that maintains Jacobsen's original design. In order to experience what may well be the only extant 20th century design hotel by a master architect, one has to book a fare to Sorrento, Italy, where Gio Ponti's Parco die Principi is very much alive and well. That's just what I did last February after a business trip to Milan. Although it was the off season (and this is very much a place to be enjoyed with warmth and sun), Parco dei Principi is a total design that doesn't disappoint.