Sea Cloud Cruises:
River Cloud, River Cloud II

ABOVE: The River Cloud II in Venice, Italy before being redeployed to its current routes between Amsterdam and Budapest.

Sea Cloud Cruises is an upscale German line with two vessels on Europe's inland waterways: the River Cloud and River Cloud II. Both ships are meant to evoke the "nostalgic charm of the 1930s" and offer some of the most luxurious river accommodations afloat.

River Cloud is currently on a long-term charter and won't be available for individual bookings in 2013.

River Cloud II cruises on the Rhine, the Main, and the Danube between late March and early November.

Americans represent a majority of the line's international clientele, and all service staff speak English.

The company also operates two classic sailing ships, the Sea Cloud and Sea Cloud II, which cruise in the Mediterranean and Northern Europe from spring through fall.