The Mosel is where Germany's most ravishingly elegant wines are made.
The region — some 21,700 acres (8,800 hectares) — is defined by the hauntingly beautiful and eerily still Mosel River, which cuts a deep, snakelike gorge through the land, entering Germany where the country converges with Luxembourg and France and winding about 145 miles northeast until it empties into the Rhine near Koblenz; the Saar and the Ruwer are its small tributaries.
The Mosel's greatest grape is riesling, but that states the case too simply, for here riesling is turned into wines of such crystalline clarity they are like glittering sunlight on a subzero day.
The reasons are several.
The vineyards are the steepest in Germany and among the steepest in the world — the stretch from Zelting to Bernkastel is considered the longest run of near-vertical vineyards anywhere on the globe, and the steepest vineyard in the world, Calmont, has a 60- to 70-degree incline that makes it look like a vertical wall of vines gripping the slatey cliff.
They are also among Germany's most northern.
Steepness in a cold, northern region means the sun is in contact with the vines for limited, precious hours each day, and the total sunlight during the growing season is modest — in a good year the Mosel gets about a third of the sunlight hours that Provence does.
So vineyards must be perfectly sited to maximise every ray, and the region's famous grey-blue slate holds heat well, helping riesling to ripen.