US, Atlanta: World of Coca-Cola tells how the world's most famous soft drink was invented

When Atlanta pharmacist Dr John Pemberton concocted Coca-Cola's formula in 1886, it was initially a fizzer. Just nine glasses a day were sold on average during the first year. He couldn't possibly have guessed that his creation, mixed in a cast-iron kettle over an open flame, would one day become world famous.

Today Atlanta, Georgia is home not only to company headquarters so large it's practically a small town (the midtown campus even has a doctor's office to look after 4700 employees) but a slick downtown museum dedicated to the fizzy drink with a secret formula.

The museum's biggest appeal for me is that you can try dozens of Coca-Cola beverages from around the globe (500-plus global brands make almost 3900 types of sparkling and still drinks; in Australia, the company offers 165 drinks across 25 brands). Like a big kid, I can hardly wait to sample exotic flavours in the Taste It! beverage lounge.

Turns out I don't have to wait for the lounge to quench my thirst. Visitors can choose a Coke – original, Diet (the first brand extension, introduced in 1982), Zero Sugar or Life (with sugarcane and stevia) – to slurp during an introduction in front of memorabilia such as a sign promoting a glass of Coke for five cents.

We shuffle out to queue for the shiny, pop-riveted Vault of the Secret Formula. Inside, the story unfolds of how Pemberton created a syrup that could be mixed with carbonated water and sold at a neighbourhood pharmacy. At the time, the most popular soda-fountain flavours were lemon, orange, vanilla, pineapple, strawberry, cherry and chocolate.

Pemberton sourced his ingredients from around the world but I don't see mention of the rumour that his formula originally included cocaine extracted from coca leaves. Instead, it's a matter-of-fact account of how his bookkeeper invented Coca-Cola's name and logo, and how fellow pharmacist Asa Griggs Candler started buying shares in 1888, becoming sole owner of the secret formula and its trademark three years later.

Candler's $US2300 investment was a smart move. By 1919, the empire was sold for $US25 million. The only time the secret formula ever left Atlanta was when Candler put it up as collateral for the loan he needed to buy the company. The formula sat in a New York bank vault for six years. Today, it's in another vault – marked by a biometric handprint panel – within this larger vault.