Debuting in 2013, the 118-passenger Queen Isabel runs routes along the Douro River, past terraced vineyards and sloping estates. Named after one of Portugal's beloved female sovereigns, the ship has lavish interiors: two suites measure 323 square feet, and 18 junior suites at 215-square-feet have step-out balconies, and all staterooms are appointed with iPod/iPhone chargers and players, L’Occitane bath products, bathrobes, and slippers.