While we here in America think of "Happy Hour" as that time in bars where we can get discounted well-drinks, in French cafes, 5pm is known as l’heure verte, or “the green hour" where green Absinthe (known as "verte") is enjoyed.
Absinthe is a spirit made from a grape distillate macerated with a blend of herbs (licorice, petite wormwood, nettle and more). The green color comes from the nettle. While Absinthe was the drink of choice in France in 1910, it was banned for many decades. In the early 2000's, the absinthe ban was repealed around the world and the green liquid started to flow again.
Absinthe is an elegant, sipping drink, not something to drink to get drunk. It is a relaxing drink that should not be rushed. In fact, Absinthe is an upper and you just can't be angry when you drink it. It is a very pure spirit and one of the healthiest you can drink.