Opened in 2009, this marble-clad cube of modernist luxury is so close to the waterfront it feels like you're on a cruise liner floating down the River Tagus. It sits in the Belém district within sight of the iconic white tower, the UNESCO-rated Jerónimos Monastery, and the galleries and concert halls of the Centro Cultural de Belém. Despite all the history around it, the hotel is rigorously contemporary. The bar and lounge have clean black-and-white lines with liberal use of leather furniture and hardwood decks. Natural light is a big feature in the public and guest rooms thanks to floor-to-ceiling windows opening out on to the water. All the rooms are spacious and airy with great views. They are even better from the corner suites, but even they can't compete with the panorama from the rooftop pool. Downstairs, the Spa by Karin Herzog has 1,000 square meters where you can relax with a massage, sauna, or Turkish bath, or work out in the gym or dynamic pool. After burning up the calories, it's safe to treat yourself in the Michelin-starred Feitoria restaurant.