We were just two people for a tour but our guide Miriam was exceptional. In excellent English she explained the process of making champagne as we toured the caves beneath. This was a gem of a find. We turned up on speck but were rewarded with one of the highlights of our holiday. Just be mindful that they are closed over lunchtime. Well worth a visit. Champagne tasting at the end with the opportunity to buy that we couldn't resist.