It’s a Canadian institution older than this country’s flag: Tim Hortons turns 50 years old on Saturday.

The coffee and doughnut chain is celebrating its half-century birthday with free birthday cake doughnuts.

Former Toronto Maple Leaf Tim Horton opened his first doughnut and coffee store in Hamilton, Ont., along with former police officer Ron Joyce in 1964.

By 1967, Joyce was a full partner and Tim Hortons was already setting up new franchises across southern Ontario. Now, the company makes more than $3 billion a year and has over 4,000 restaurants in Canada and the United States.

Earlier this week, Tim Hortons gave Toronto customers a blast from the past as it transformed Yonge and Dundas Square into a scene from the 1960s – the era in which Tim Hortons was founded.

The company had old-timey cars, 1960s fashion and a replica of the first Tim Hortons restaurant set up in the Square.

And while Maple Leafs legend Tim Horton couldn’t be on hand for the 50th anniversary celebration (he tragically died in a car crash in 1974), there were still a few former members of the Blue and White on hand for the festivities, including Johnny Bower, Ron Ellis, Darcy Tucker and Wendel Clark.

The Tim Hortons brand has changed plenty over the last five decades. Originally conceived as a coffee and baked goods store, the company has ventured into the deli sandwich and fast food breakfast markets in recent years. Nowadays, it’s trying its hand at fast food with products like the chicken wrap and chicken sandwich, while also attempting to cater to higher-end coffee drinkers with new latte options.

It’s also faced challenges from fast-food competitors like McDonald’s, which has pushed hard to take a piece of the coffee market in recent years. McDonald’s has staged a number of free coffee days to combat Tim Hortons’ annual Roll-up-the-Rim promotion.