Champagne Mercier was founded in 1858 by Eugene Mercier, who set out to bring champagne within reach of the middle classes rather than reserve it for kings. The 18-kilometre cellar network beneath the property is one of the largest in Epernay, and Mercier's signature tour takes visitors through it by little electric train rather than on foot — a slightly kitsch but genuinely fun experience.
The cellars are decorated with carved-chalk reliefs commissioned by Mercier himself in the late 19th century. Tours include a glass of brut at the end; longer tastings and food pairings can be booked.