The Crystal Debussy on the Rhine River in Germany. Photo Credit: Crystal River Cruises Crystal River Cruises has scheduled its deployment for 2021, with the luxury line opting to use two of its five ships to sail 35 voyages ranging from seven to 11 nights. The Crystal Ravel and Crystal Debussy will return Aug. 29 and 30, respectively, sailing the Rhine, Danube and Moselle rivers. Every voyage will have at least two overnight stays, and some will have three. Crystal said its Christmas Market voyages are sold out and that there is limited availability on the other 2021 cruises. Crystal River Cruises senior vice president and managing director Walter Littlejohn said there is "pent-up desire to cruise to iconic cities such as Amsterdam and Budapest and epicenters of art and music such as Vienna and Salzburg, paired with the dramatic landscapes and natural beauty of the Wachau Valley and Middle Rhine Valley."