They call it "a bridge too far".
Plans to build one of Germany's biggest bridges and a four-lane motorway through the Mosel valley, where the celebrated Riesling wine is produced, have outraged local wine-makers and international wine critics alike.
For a wine lover, the winding Mosel valley is as close as it comes to paradise. In bright sunshine, the world's best Riesling vineyards resemble a green patchwork stitched to the steep hillsides.
Because of the impossible angles, the vineyards are tended by hand, just as they were in Roman times.
Near the village of Graach, sunburnt farm-workers crunch the slate-rich soil underfoot as they move in tandem, gingerly pruning young shoots.
But just round the river bend, bulldozers are busy tearing into the reddish earth.
This is the chosen site for a massive motorway bridge.
Known as the Hochmoseluebergang, it will be 160m (525ft) high, 29m (95ft) wide and 1.7km (one mile) long.
The bridge has been in the works since the Cold War, when American troops based in Germany wanted a quicker route to the rest of Western Europe.
Recently revived as part of the economic stimulus package, it will cost some 270m euros (£223m).
For Ernst Loosen, one of the region's leading wine makers, it is the last thing the Mosel valley needs.
"The skyline of the bridge will be higher than the mountains," he complained.
"We're very worried about tourism, because people come here for the beauty and not to look at such an ugly construction."
But he is also concerned that the building work for the four-lane motorway will cut off the water supply from the forest on the edge of the hills to the vineyards below.
Ernst Loosen's family has made wine here for more than 200 years.
In a last-ditch attempt to stop the bridge, local campaigners like him have enlisted the support of the Green Party and sent the German parliament a petition with more than 11,000 signatures, including some from as far as California.
Mr Loosen exports Riesling wines to 62 countries around the world.
"This year I've been travelling to New Zealand, Australia, Asia," he said. "Everybody I met was totally worried and said: 'This is such a beautiful valley, it's such a treasure these vineyards, how can you do this?'"
Prominent wine critics have also joined the fight to rescue the Riesling. The best-selling author Hugh Johnson calls it the ultimate white wine.
"If you've got a lot of flavour in a light wine, that is ideal," Mr Johnson explained.
"The Mosel is the only place that does that - eight degrees alcohol and a whole bunch of flavour. Now that is magic and it's unique. And here is the very best vineyard, and they're going to drive a motorway through it? It's like knocking down a cultural monument!"
But on a sunlit terrace overlooking the Mosel valley, some are toasting the project.
Patrick Philipps, who runs the Philipps-Eckstein winery in Graach, describes it not as a disaster, but an opportunity.
"I agree the bridge interferes with nature, but it will bring more people from Belgium and Holland, and shorten travel times from other parts of Germany," Mr Philipps said.
Those arguments are entirely to the taste of Hendrik Hering, the minister for wine making in the state of Rheinland-Palatinate, where the Mosel valley lies. Mr Hering also happens to be the minister in charge of transport.
The bridge is indispensable because it will cut travel time by half an hour between Germany and the Benelux countries and ease the flow of traffic, he insists.
"Over 20,000 cars cross the Mosel valley, a quarter of them lorries," Mr Hering said.
"We need an efficient east-west connection. The valley would be disrupted more if we allowed thousands of vehicles in and out every day."
But would the minister describe the design of the bridge as beautiful?
Mr Hering gave a cautious answer: "A bridge of this height and size certainly cannot be described as pretty. It serves a purpose. We'll try to make it slender, but we need it for our infrastructure."
Wine lovers can only hope they will enjoy the new bridge as much as they enjoy the Riesling.
But there is still a concern it could disrupt the delicate balance of the Mosel valley and its unique white wines.