Only two monks of the Grande Chartreuse monastery, not far from Grenoble, know the recipe of the "elixir of long life" developed in 1737 by a Carthusian friar, Jérôme Maubec. A tour includes a visit to the cellars, home to the oak barrels where the liquor is aged for several years and the hi-tech stills in the distillery; it finishes with a tasting of this 70° proof elixir!