The caves of Bernard-Massard are the obvious starting point for any visit to Grevenmacher. This long-established sparkling wine producer offers guided tours of its underground cellars, explaining how Crémant de Luxembourg — the country's answer to Champagne — is made using the traditional method of secondary fermentation in the bottle. The caves themselves are atmospheric: low tunnels lined with thousands of bottles in various stages of ageing, all at a steady 12°C.
The tour ends with a tasting of several wines in the reception room. Bernard-Massard is the most visited winery in Luxembourg and polished enough to handle coach parties efficiently, but it doesn't feel impersonal. The guides clearly enjoy talking about the wine, and the tasting is generous. If you want to take some home, there is a well-stocked shop at the exit.