Solo traveler cruises will also expand from the Danube and Rhône rivers to the Douro River.
'These exclusive departures for solo travelers offer the opportunity to experience a European river cruise on a five-star ship with like-minded travelers, without paying a single supplement for any cabin or suite across the entIre ship,' said Jana Tvedt, the line's US VP.
Eight-day cruises start at $2,099
'The Douro, Porto & Salamanca River Cruise for Solo Travelers,' an eight-day program, sails March 31. Fares start at $2,599.
'The Blue Danube River Cruise for Solo Travelers,' also eight days. departs April 1 and Oct. 28. Fares begin at $2,099.
And the eight-day 'Burgundy, the River Rhône & Provence River Cruise for Solo Travelers' sails Oct. 31 and is priced starting at $2,419.
Some no-single-supplement cabins on every cruise
Besides these cruises, every Riviera departure throughout the year sets aside a limited number of cabins with no single single supplement.