Cabins with double beds Many 'double' cabins have twin beds. These boats have at least some cabins with double beds.
Single cabins It usually costs less to have a single cabin to yourself then a double cabin just for you.
Suitable for families These boats make a point of welcoming, and providing for, families with children on at least some of their voyages.
Private balconies When sea conditions are right, it's wonderful to be able to step straight out from your cabin to watch a passing orca pod, take a photo, or see the dawn break. These ships have at least some cabins with their own balconies.
The use of some facilities may require advance booking or involve an extra charge.