Contrary to what is found all over the Internet on the subject, the most common drink was water, for the obvious reason: It's free. Medieval villages and towns were built around sources of fresh water. This could be fresh running water, a spring or, in many cases, wells. All of these could easily provide fresh, disease- and impurity-free water; the idea that water from these sources would be the causes of disease and so had to be made into ale or beer is fanciful.
Where water was more likely to be contaminated, largely by tanning, slaughtering, or dying facilities, was in larger towns. But since medieval people were not idiots, they dealt with this in several ways. There were ordinances on where tanners and dyers could operate so that water for domestic use could be drawn from rivers and streams in the town to ensure the water was clean. And there were fines for contaminating areas of streams used for household consumption.
In larger cities, water-supply infrastructure was built to ensure public access to clean water. In medieval London, for example, the City Council began construction on what was called "the Great Conduit" in 1236. This was a complex of pipes that brought water from a large fresh spring at Tyburn to a pumping house with cisterns at Cheapside. This fed local cisterns all over London.
Wealthy Londoners could apply to have a private pipe or "quill" run from the conduit system to their house, giving them running water. This was expensive, and citizens who illegally tapped into the conduits were severely punished. Most people either drew their water from the nearest conduit cistern or paid a "cob" or water-carrier to bring them their day's water supply in three-gallon tubs, which they carried through the streets on a yoke. Public celebrations, such as the return of Edward I from Palestine or the coronation of Richard II, saw the city stop the water flow and fill the conduits with wine for the day, with people able to drink as much as they wanted.
People did drink a lot of ale and beer, but not because their water was so bad. The brews in question were much weaker than their modern equivalents but had the effect of providing much-needed calories to laborers and farmers, as well as being thirst-quenching and re-hydrating in hot weather or when working hard and losing sweat. Given the long days medieval workers put in, ale and beer were a major and necessary part of a laborer's daily energy intake. This should be seen as something like the medieval equivalent of drinking Gatorade.
Wine was the drink of choice for the upper classes and anyone who could afford it. It was produced all over medieval Europe and, due to the Medieval Warm Period that prevailed over western Europe until the 14th century, the climate meant it could be produced as far north as northern England. Wine was expensive and buying a small barrel was beyond the means of most people. But taverners bought it in bulk and sold it by the cup, so for a penny or even a halfpenny, an English peasant could enjoy a Bordeaux red.
In medieval England, the wine drunk most was red wine from Bordeaux and Gascony. Rhenish white from the Rhineland was twice as expensive and favored by the upper classes. Spanish white wines such as Lepe and Osey were cheaper and sweet wines from Greece, Crete, and Cyprus such as Romonye and Malmsey were popular after dinner.
Ian Mortimer, (2011)
"The Great Conduit in Westcheap" from The Dictionary of London (1918)
" " in Floregium Urbanum, (2001-2011)
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