New Years Eve cruises at Silvesterschiff.de on the Rhine River near Bonn and Mainz can still be booked online.
Winter cruises available at Winterfahrplan.de, plus Christmas parties and Advent cruises on the Lower Rhine, Middle Rhine, and Main.
Even during low water: Wine tasting cruises available Sundays for groups of 4+ in the Rheingau (via Weinprobenschiff.de) and daily for groups of 10+ near Rüdesheim.
All Rhine in Flames 2027 can be booked.