There are good reasons (all of which hold water) that European river cruises operate between April and October. The Rhine glistens like a glass of the local riesling during the height of a European summer, there's less chance of rain and there are lovely long days - perfect for sightseeing up on deck. But there's more to the Rhine than summer wine for, in the deep of winter from November to late December, Christmas markets ring in the festive period and add a very different flavour to a cruise through German towns and villages.
Most Rhine river cruises are seven-to-10-night affairs, between Basel (fly into Zurich) and Amsterdam in the Netherlands. Tucked into Switzerland's top pocket, Basel is close to the Dreilandereck, an area where Switzerland, Germany and France meet along the Rhine. The river forms the border of France and Germany, and sweeps through Upper Rhineland, a region of small slant-roofed towns edged by vineyards.
There's usually a stop in the French city of Strasbourg, with its sandstone cathedral and market squares. The French border is south of Karlsruhe and many cruises then dock at Speyer for an excursion into the old university town of Heidelberg. At the confluence of the Rhine and Main is Mainz, the centre of Germany's wine economy.
The Rhine tracks on through some of the most sublime views on any of the world's rivers and north-west of Mainz, the waterway snakes on an inverted "S" through the Rhine Gorge. It is a chocolate-box scene where a succession of gorgeous half-timbered towns line the banks, in front of vineyards which sweep steeply away from the river. Old castles and fortresses in various states of repair punctuate the horizon to the east and a visit to castles such as Marksburg at Braubach is usually an included excursion on a cruise - in July and August, the long evenings are lit up here by fireworks displays.
The river continues through Koblenz, where the Moselle joins the Rhine under the shadow of the imposing Ehrenbreitstein Fortress, one of Europe's biggest castles, on the eastern bank, while in the west is the wide promontory of Deutsches Eck settled by the Teutonic Knights in 1216 but today dominated by a statue of Kaiser Wilhelm I on horseback. To the north lie Bonn, the capital of the old West Germany, and Cologne, where the cathedral spires reach up 157m atop a dramatic edifice which took 632 years to finish. The river meanders into the low-lying Netherlands through Arnhem, with its open-air museum of Dutch life, to end in Amsterdam. There are a number of variations to cruises along the Rhine. Mid-cruise at Koblenz, some itineraries veer east along the Moselle to Cochem and the Reichsburg imperial castle, and to the wine-growing centre of Bernkastel where there may be an excursion to the tiny Grand Duchy of Luxembourg. Some itineraries end in Rotterdam in the Netherlands or in the Belgian capital Brussels. Another option is a round-trip cruise from Amsterdam taking a circular route through North Holland, famed for its tulip fields, the dairy country of Friesland and the old shipbuilding centre of Batavia.
Christmas itineraries usually extend along the Rhine between Basel and Cologne, visiting markets and taking part in festivities in Strasbourg, the Black Forest, Heidelberg, Rudesheim, Koblenz and Cologne over the course of five to eight days. Yuletide cruises are extremely popular and sell out a long way in advance.