The ancient coastal city of Thessaloniki is speckled with fascinating art galleries, but just one of them, The Met Hotel, doubles as an extravagant hotel. Wandering through its roomy, avant-garde hallways, it's hard to believe people are actually allowed to sleep here. On the piano-black walls, there are bold shots by famous fine-art photographers. And in the generous public spaces, you'll find sculptures and video works by some of the world's most revered contemporary artists. The floors of the 212 seductively simple rooms and suites are decked in dark tropical timber, and sea views flood in through huge glazed panes. A feeling of quality and intimacy washes over you as you sink into the swooping, softly lit sofas at Chan, the hotel’s zesty Asian restaurant. There is an indulgent spa too, but eventually the real joy is in exploring The Met's intriguing collection of artwork.