Kakslauttanen Arctic Resort - The famous Glass Igloos in Finland are definitly one of the most romantic Hotels of the world. Sleep under the Stars and in one of the world's best places for watching the Northern Lights.
Maldives is the ultimate island destination. Many resorts are their own islands and feature personal cabanas attached by plank walkways over the water. See the famous bioluminescent phytoplankton beaches on Vaadhoo Island at night that look like an ocean