“What do you know about Lyon ?” Pretty much what the dictionary says. It is the third largest city in France, spread over two hills and on the banks of two rivers: the ill-tempered Rhône, which is difficult to temper, and the gentle Saône. Lyon is the industrial capital of the south-east, with a commercial vocation that has been symbolised by its trade fairs for several centuries. It’s a strange setting for a detective story, but it’s also an almost Florentine city under a southern sun. Did you know that Lyon was the birthplace of two Roman emperors, Claudius and Caracala, and a few centuries later became the eldest daughter of the Church? Cinema itself was born in Lyon. It is also the French capital of gastronomy, and Lyon’s cuisine has benefited from its privileged location. And then there’s wine, Lyon’s third river, according to the canus (silk factory workers) who know their stuff. Renaissance towers adorn the courtyards and gardens, and you only have to step into the shadows to find these places where Lyon, a learned city, piously preserves its memories.