Our tour along the Burgundy Canal culminated at Tonnerre, a quaint town of over 2,000 years old. Although it has a fair few sites for a small place, it is best known for two of them in particular. The first of these is the Hôtel-Dieu Notre-Dame des Fontenilles
situated on the square named after its founder Marguerite de Bourgogne, queen of Naples and sister-in-law to Saint Louis. Built at the tail end of the 13th century, the hospital was intended as a place of refuge for the ill and vulnerable as well as for widows and pregnant women, although lepers and the plague-stricken were not admitted. It continued to be a place of shelter right up until the middle of the 16th century when humidity and heating problems caused it to close and to become a church. The main room, known as the Salle des Malades
, or Room of the Sick, was originally 100m in length, 18m wide and 18m high. One can still observe the original timber roof structure although much of the rest of the building has been restored. Visitors can visit the tomb of Marguerite as well as the gnomon which still functions today and a painting of Christ being laid to rest. A museum dedicated to the hospital is housed in what used to be a second, smaller hospital and which displays the original charter as well as some religious art. The Hôtel-Dieu is open every day (except Wednesdays and Sundays between 15th October and 15th April) and is adjacent to the tourist office where more information is available.
The second must-see attraction in Tonnerre is the Fosse Dionne, a meteoric karst spring which results from the infiltration of precipitation into the calcium plateaus of the surroundings. It has been a source of mystery and considered divine for thousands of years and in fact the town was built around it. In 1758 in was turned into a wash-house and today still provides Tonnerre with water of an exceptional quality. It has a large hydrogeological network estimated at around 27 miles and many have dived in over the years to explore it and bring up various remnants of years gone by. Some, sadly, lost their lives in doing so, it being one of the most difficult to navigate for various reasons.