Ahr is one of Germany’s least-known and northernmost wine regions. It lies immediately north of the Mosel, and follows the Ahr River in the final stages of its journey towards its confluence with the mighty Rhine. One might expect a wine region this far north (50°N) to specialise in white wines – like almost every other cool-climate wine region. After all, neighbouring Mosel and Mittelrhein both clearly favour white wines. But Ahr turns the tables completely, producing around 85% red wines, of which around three-quarters are made from Spätburgunder (Pinot Noir). The classic Ahr Spätburgunder is brick-red in colour and smells of red cherries, sweet spices, forest floor, possibly with a hint of smoky bacon fat if barrel-aged.

Ahr Pinot Noir is now a much more serious, modern and "international" wine style that it once was. Until 30 years ago, the wines were often slightly sweet and very pale. Today they are invariably dry and deeper in colour – although still much paler than the ink-dark Pinots found in, say, Central Otago. As is the case in various parts of Germany (most obviously Pfalz and Baden), the popularity of Pinot Noir has been steadily increasing here over the past few decades. The wave of interest has carried German Spätburgunder to new heights, and saved from near-extinction the earlier-ripening Pinot Noir clone, Frühburgunder.

Other significant varieties in the Ahr vineyards are Riesling and Portugieser. Ahr Rieslings vary considerably depending on the vineyard site they come from. Those from sunnier, warmer sites tend to show rich fruity aromas of baked orange, peach and lime zest. Those from cooler, more shaded areas are closer in style to Mosel Riesling: lighter, lemony and more mineral. The local Portugiesers are quite different from the Pinot Noirs; they seem fruitier, juicier and sweeter with lively aromas of blueberries and roses.

The Ahr region's annual wine output is tiny. In 2014, the region’s entire vineyard area amounted to just 1345 acres (545ha). This is just 6 percent of the area under vine in neighbouring Mosel, and a mere 2 percent of that in Germany’s most prolific wine region, Rheinhessen. Yields are significantly lower here than in other German wine regions; the average vine growing in the Mosel produces about 25 percent more wine than one in the Ahr. Unsurprisingly, Ahr wines are quite rare, and are pretty hard to find outside Germany. The main Ahr wine producers whose wines do make it onto export markets in any quantity include Deutzerhof, Brogsitter, J.J. Adeneuer, Jean Stodden and Weingut Meyer-Nakel.

In the cool northern German climate, sunshine is of vital importance. Without it the grapes stand little or no chance of ripening fully. Thus the best Ahr wines come from steeply sloping vineyards that face roughly south and are able to capture high levels of sunshine.

Even within a region as small as Ahr, there are significant variations in landscape and mesoclimate. At the region’s western, higher end, the vineyards are located on steep slopes punctuated by craggy, rocky, outcrops and surrounded by dense woodland. Throughout the day the sunshine warms their dark volcanic soils, which retain the warmth into the night, levelling out the temperatures somewhat. The woodland-capped hills and craggy outcrops also offer protection from the cold north winds, which would otherwise whip the warmth away. At the region's mid-point, the river makes tight, sweeping turns around the villages of Mayschoss, Rech and Dernau, before sweeping around one last tight bend into Walporzheim. After Walporzheim the valley widens out into flatter, gentler terrain towards Neuenahr-Ahrweiler, Heimersheim and finally the Rhine.

The Ahr river itself is narrower than the Mosel, and the slopes above it are rarely as high. In Piesport, at the very heart of the Mosel, the vineyard-lined slopes rise up to 980ft (300m) above sea level. Here in Ahr, only a tiny number of vineyards (in Altenahr, Maychoss and Dernau), reach this high.