Over 250 bars and restaurants serve Guinness across the Valley, and over 3,000 such establishments have it on tap across the state. Celebrating its 250th anniversary, both the drink and its history are rich and thick. It's brewed from the same four basic ingredients—malted barley, hops, yeast and water—Arthur Guinness first concocted at St. James Gate in Dublin, and modern day brewers are fastidious about maintaining tradition. The water is still drawn from the same well in the Wicklow Mountains near Dublin, and they still brew from the same strand of yeast, the source of which is kept in vaults around the world to which only five master brewers have access. Guinness also comes in several varieties: the most popular draft version is available drawn from the tap, but also in cans and bottles, thanks to a technology the brewer invented. But it is also available as Extra Stout, a bottled version, which has been available since Guinness first came to America in 1967. Unlike the draft version, it's carbonated and higher in alcohol. Another, even stronger variety is only available elsewhere in the world and is particularly popular in Africa. Though Guinness draft does not include the word "light" in its name, the beer is actually almost 10 calories lighter than most calorie-conscious beers.