Mosel, major German growing region with 8,776 ha/21,676 acres of vineyard in 2013, formerly known as Mosel-Saar-Ruwer. It is associated with long-lived wines of delicacy and dynamic complexity, including some of the world’s finest sweet wines. The total area planted has been declining slowly and, except in the best-known vineyards, Riesling grapes command a price that only just covers the costs of farming the generally steep, stony, sheer slopes with their densely planted and often archaically trained vines. (See germany, Viticulture.) As the River Mosel twists from Trier to Koblenz, the vineyards are at their steepest on the outer edge of the curve. Those on the flatter inner edge are frequently planted with varieties other than Riesling on land more suited to agriculture than to viticulture. topography is all important here, but soil, too, is critical. Virtually every top Mosel, Saar, or Ruwer site is dominated by Devonian slate, which has been used in the region for hundreds of years as a building material. Even vineyards naturally short of slate have had it added to help retain warmth. Some of the vineyards between the almost vertical spurs of rock were created in the 16th century with the aid of explosives, a dangerous operation when there was a wine village below. Vineyards have been subjected to the wholesale renovation known as flurbereinigung) later and to a lesser extent than those of most other German regions, the principle obstacle being sheer steepness and difficulty of access to the slopes for earth-moving equipment, whose production costs remain among the highest in Germany. Vineyards associated with some of the Mosel’s most important villages also proved resistant to the late-19th- and early-20th-century ravages of phylloxera, and in those places many vines are ungrafted (and could until very recently be replanted without grafting), a dwindling but arguably precious legacy.