The traditional Russian drink, kvas, is making a comeback. Sales of this thirst-quenching, beer-like beverage are soaring this summer after years of decline. Multinationals and small monasteries alike are rushing to cash in on the craze for this classic

Kvas is a fermented “bread drink” that tastes a bit like a weak beer or wheat cider.  Its origins go back 5,000 years to the beginnings of beer production. It was first mentioned in the Old Russian Chronicles in the year 989.

For centuries in Russia it was the most common non-alcoholic drink in every class of society. In the 19th century, it was reported to be consumed in excess by peasants, low-class citizens, and monks. Sometimes it was usual for them to drink more kvas than water.

The alcohol content is so low (0.05-1.44%) that it is considered acceptable for consumption by children.

For over 600 years, monks at the Savvino-Storozhevsky monastery in Zvenigorod near Moscow have been brewing the beverage for themselves. But seven years ago, they decided to share their drink.

In a basement beneath the onion domes of the town's 15th-century Orthodox monastery, a huge refrigerator chills the brew.

“Kvas is a Russian drink which appeared here during ancient times. It is made from plants that grow on our land. And the taste that kvas brings, is pleasant for Russians,” Father Antony said, a Monk at Savvino-Storozhevsky monastery.

Different brewers are bringing their own qualities to kvas. This one says the beverage he makes is “live” and some people even drink it for medicinal purposes.

Despite the drink’s humble folk origins, it has recently become a booming multi-million dollar industry.

Once it was only sold during the summer from wheeled yellow tanks the size of beer barrels, now it is bottled or canned.

For many Russians it brings back memories of childhood and evokes feelings of tenderness.

Western imports like Coca-Cola and Pepsi once stifled the commercial kvas market. But now Coca-Cola has launched its own version of Kvas.