'What's in a name?' asked England's most famous bard. Not much, the winemakers in Mosel-Saar-Ruwer, arguably Germany's finest wine region, would say as they've decided that including the Saar and Ruwer rivers in their titles is too cumbersome. From this year's vintage onwards (on our shelves next year) they will simply be labelled Mosel. The change of name has not altered the region's geography and its vineyards will continue to be found along the shores of three rivers, the Mosel, Saar and Ruwer (pronounced MOH-zehl, Zahr and Roo-vehr). A writhing, spiraling, serpentine body of water, the Mosel travels 240km to cover about half that distance as the crow flies before emptying into Germany's Rhine River. The most important wine estates are concentrated in the Mittelmosel (middle Mosel); villages such as Bernkastel, Piesport, Zell, Brauneberg and Wehlen have centuries-old reputations for the finest light wine in the world - and more recently for their Christmas markets. Rooted in one of the world's most northern wine regions (50 degrees latitude), the Mosel vines struggle to find warmth in conditions even chillier than those in France's Champagne region. The shivering vines are planted in tightly spaced, slim terraces - in many cases comprising only a single row on arguably the steepest vineyard sites in the world - with the hope of capturing reluctant rays of light. The steepest vineyard in the valley is Calmont, where the vines are planted on a 76-degree incline. Slate stone is the key to Mosel's fine quality, argue the locals. The vineyards are littered with shards of this slippery, silver-grey material, which is credited with reflecting the sun's rays to help ripen the grapes as well as absorbing and storing heat to keep the vines warm in the evenings. Slate is so valued by the Mosel vineyard owners that after heavy rains they haul bucket-loads of it up slippery slopes to replenish stocks that have washed down the hill. Like most of those in Germany, Mosel wines are primarily white, with riesling dominating the prime real estate. The less spectacular Muller-Thurgau (15 per cent of plantings) produces a simple, fresh, fruity wine popular with locals and Elbling (9 per cent of plantings) a 'cheap and cheerful' sparkling wine called sekt. Ranging from bone-dry to the densely sweet Trockenbeerenauslese, Mosel riesling is admired for its gossamer character, crystalline fruit purity, light alcohol levels (7 to 9 per cent) and stiletto acidity. By tradition, Mosel riesling is bottled in tall blue-green flutes and thanks to its high acidity can develop in these slim bottles for decades before peaking. Top sites include the three sonnenuhr (sundial) vineyards, so named because huge sundials were erected at the sunniest spots on these premium slopes more than a century ago so vineyard workers would know when to stop for their mittagessen (noon meal). Eventually the slopes around the sundials became some of Mosel's finest vineyards: Wehlener Sonnenuhr, Brauneberger Juffer-Sonnenuhr and Zeltinger Sonnenuhr. Unpronounceable at first glance? Perhaps, but what's in a name, so long as you can point at it. An excellent selection of Mosel wines is available at Rare & Fine Wines in Central (shop L6, lobby floor, The Bank of East Asia Building, 10 Des Voeux Road) and in Kowloon (shop 11, G/F, Hankow Centre, 5 Hankow Road, Tsim Sha Tsui).