One hundred years ago, a Swiss from the canton of Thurgau developed a crossbred grape. It was named after him, the Muller-Thurgau. The anniversary is being celebrated at Geisenheim, Germany's leading wine institute, where Muller worked and where his spiritual heir, Prof. Helmut Becker, continues to develop crossbreeds. The new grapes have names like reichensteiner and ehrenfelser, after castles on the Rhine, or osteiner, a fitting honor for an aristocratic family, now all gone, "boozed-out" according to Becker.

The links with the past that are present in all European winelands are nowhere more entwined than in Germany. At Kloster Eberbach, in the hills above Eltville, the cold, bare walls and cloisters built by Cistercian monks warm and soften when decorated for the annual harvest service, or when the stillness is broken for the twice yearly wine auctions. Here is the original kabinett cellar, where an 18th-century carpenter built a cabinet for the monks to store their best wines.

At Schloss Johannisberg, there's a statue of the rider who carried the required, but belated, permission of the region's bishop to pick the grapes. So belated was it, the grapes were overripe, thus making the first recorded "spatlese."

Trier, the central city of the Mosel wine route, was occupied by the Romans 2,000 years ago. There's a three-story deep Roman wall in the wine cellars of the Vereinigte Hospitien (United Hospitals). The Hospitien itself is comparatively youthful, formed by a Napoleonic edict of 1805.

The Napoleonic Code, whereby property was divided equally among all heirs, has left a legacy from which growers in the Mosel-Saar-Ruwer are now extricating themselves. They call it reorganization: the consolidation of ownership of the tiny patches of vineyards into more-manageable sizes.

Reorganization for economic reasons is also taking place along the Rhine, but it has been harder to manage in the Mosel, where no machine can get into the upper vineyards. On the gentler slopes of the Mosel and in the Rhine, vineyards are being replanted with wider spacing to allow tractor cultivation. As a modern touch, spraying is usually done by helicopter.

In the old cool, damp cellars of the prestigious estates, there's been one general change in winemaking. Producers prefer to bottle young, within eight months or so of the harvest, to ensure that the wine retains its freshness.

Bottling younger doesn't mean drinking younger. The strongest lesson I learned on my recent visit was that German wines do benefit from more than a couple of years of bottle age, no matter whether they're kabinetts or auslesen. A '77 Lorcher Pfaffenwies Riesling Kabinett of Peter Breuer's Schwannenkellerei was an example of a wine of an undistinguished year softening into a dry, but not overly tart wine. A '71 Piesporter Domherr in Goldtropfchen Riesling Beerenauslese, von Kesselstatt, could wait another six years. And a pair from the '50s were in perfect, soft, rich, condition: a '59 Wehlener Sonnenuhr feinste Auslese, Joh. Jos. Prum, and a '53 Bernkasteler Doctor Auslese, Dr. Thanisch.

Aging a German wine, like aging any wine, depends on its initial quality, of course. Thanks to the generosity of producers up and down the two rivers, I tasted many wonderful wines, too many to list. There is space to mention that, should you chance upon a well-handled '71, you're in luck. With less hunting, you can still find some '75s and '76s. In general, I prefer the '75s, liking their crispness, their higher acidity, rather than the atypically rich wines of the drought year of 1976. Not many spatlesen were produced in '79, but the kabinetts are delicious summer drinking right now.

Then, cross fingers, thump wood and hope that this year's harvest will be as big and as beautiful as it looked in July.