From historic controversy to Victoria Day disasters, the weekend known in Canada as the unofficial start of summer is our oldest state holiday. Here are 24 facts about May 24, just in time for reading on what's lovingly referred to as "May two-four."

1. Why we celebrate

A 2015 survey of 1,000 people by Canadian family history website Ancestry.ca suggests that almost half of the respondents didn't know why Canada celebrates Victoria Day. According to the website, 12 per cent of respondents thought the first long weekend in May was meant to mark Memorial Day in the U.S., while another 36 per cent said they had no idea.

The May 24 weekend is considered the unofficial start of summer in Canada: barbecue is big on the long weekend. (Gerald Herbert/Associated Press)

2. Unofficial start of summer

It's a popular time for travel. Highways across the country clog with traffic as people open up cottages and visit other summer getaway places. Police forces across the country often use the time of year to mount safety enforcement campaigns to curb highway and boating accidents, which can spike over the long weekend.

3. Victoria Day has many names

Officially, it's referred to as Victoria Day or the sovereign's birthday, but many people call it "the May 24 long weekend," "the May long weekend," and nicknames such as "May long" or "May two-four." Two-four is also another nickname for a 24-bottle case of beer.

4. Canada's oldest state holiday

According to the federal government, May 24 was first declared a holiday by the legislature of the Province of Canada in 1845 to celebrate Queen Victoria's birthday.

5. Queen Victoria was key

Queen Victoria was Canada's sovereign at the time of Confederation in 1867. The fathers of Confederation could not create the new country without her royal assent. She is also credited with turning Ottawa into the nation's capital a decade earlier.

In 1857, it was just a small logging town far away from the cities of Quebec City, Montreal, Kingston and Toronto. But the selection of Ottawa was strategic. Ottawa was on the Ontario-Quebec border and was considered a compromise between rival anglophone and francophone politicians. It was also far from the U.S. border and surrounded by dense forest, which military advisers saw as an advantage in the case of a U.S. invasion.

Ottawa was a strategic choice by Queen Victoria as Canada's capital in 1857, because it's on the Ontario-Quebec border. (Canadian Press)

6. Became annual holiday in 1901

When Queen Victoria died in 1901, Parliament made her birthday an annual holiday. The law initially called for the holiday to be celebrated every year on May 24. Unless the date fell on a Sunday, in which case Victoria Day would be celebrated on May 25.

7. Why it's not always May 24

In 1952, Parliament declared that Victoria Day would be celebrated on the Monday before May 24 every year. As a result of this convention, the long weekend sometimes falls well before May 24. This year, for example, May 24 falls on a Sunday, but due to the parliamentary decree, the long weekend will run from May 16 to May 18.

8. Queen Elizabeth's birthday celebrated

Since 1953, Victoria Day has been recognized as the official birthday of Queen Elizabeth II in Canada. In England, it's celebrated in June, even though she was actually born in April.

Queen Elizabeth visits Edmonton on May 25, 2005. (Canadian Press)

9. Queen Elizabeth's birthday visit

During her reign, Queen Elizabeth has celebrated her official Canadian birthday only once, when she visited Edmonton in 2005.

10. Not entirely Canadian

While some believe Victoria Day is a uniquely Canadian institution, it is also celebrated in parts of Scotland, where it's observed on the Monday before May 24.

While the Union Jack is traditionally flown at government buildings on Victoria Day, official protocol states it may only be flown "where physical arrangements allow." (Canadian Press)

11. The Union Jack flown

The United Kingdom's national flag, known also as the Union Jack, makes an appearance at public institutions on Victoria Day. It is traditionally flown on Victoria Day with the Canadian flag at federal buildings, airports, military bases and other government establishments within Canada "where physical arrangements allow," according to the federal Heritage department. That means at least two flag poles must exist and the Canadian flag is never replaced by the Union Jack. "If only one pole exists," the official government protocol states, "no special steps should be taken to erect an additional pole to fly the Union Jack for this special day."

12. May 24 is time to get dirty

Victoria Day is generally considered the time to start planting gardens. "For warmer parts of the country," says Environment meteorologist Geoff Couslon, "frost advisories are issued, as required between May 7 and October 30. For parts of the country whose climate is not as warm, the timeframe for when frost advisories would be issued would begin later and end earlier."

13. One of Canada's worst marine disasters

In 1881, the celebration of Queen Victoria's birthday was marred by the deaths of 182 people who drowned in London, Ont., after the "Victoria" — a double-decked steamship stuffed with 600 people — overturned on the Thames River. Accounts say that passengers rushed to the side of the ship to greet people on another riverboat. The shift in weight aboard the crowded boat caused the lower deck of the Victoria to become partially submerged. The crowds then rushed to the other side of the boat, toppling the ship.

A photo of the aftermath of the 1896 Point Ellice Bridge Disaster, which killed 55 people in Victoria, B.C. (Vancouver City Archives)

14. Victoria Day ghost story

On May 26, 1896, the last day of Queen Victoria's birthday celebrations in Victoria turned tragic when a streetcar crowded beyond capacity attempted to cross the Point Ellice Bridge. The structure collapsed under the weight of the tram and the 142 holiday revellers aboard, killing 55 people. The disaster is the origin of more than one local ghost story. According to Point Ellice House, a local museum devoted to the Victorian era, a red light can sometimes be seen under the current day bridge. It is said the light has no source and is believed to be a ghostly presence still searching for a lost relative.

15. May 24 is date that really counts

On May 24 1918, Parliament passed the Statistics Act. It created the Dominion Bureau of Statistics, which we know today as Statistics Canada.

16. Women won right to vote

Legislators gave Canadian-born women over the age of 21 the right to vote (in federal elections only) on May 24, 1916. Manitoba followed suit that same year, with other provinces giving women the right to vote in 1918 and 1922, with the exception of Quebec. That province didn't give women the vote until 1940.

Walkerton Mayor David Thomson stares at a pitcher and several glasses of water before a speech on his town's tainted water tragedy in the summer of 2000. (Tom Hanson/Canadian Press)

17. Walkerton's deadly E. coli outbreak

On May 24, 2000, four people — three adults and a baby — died from E. coli poisoning in the quiet town of Walkerton, Ont. The death toll later rose to seven people in all, and hundreds became ill from tainted water. The next day, the local medical officer health stunned the country when he told CBC Radio that it could have been prevented. He said the Walkerton Public Utilities Commission knew there was a problem with the water several days before and it could have warned the public.

18. Not a paid holiday in Nova Scotia

Nova Scotia does not recognize Victoria Day as a paid public holiday. That means employers don't have to give their employees a paid day off, and retail stores aren't required to close.

19. Or New Brunswick

While New Brunswick doesn't recognize Victoria Day as a paid public holiday, the province does consider it a day of rest.

20. Or Newfoundland and Labrador

The government of Newfoundland and Labrador only recognizes six paid public holidays: New Year's Day, Good Friday, Memorial Day (Canada Day), Labour Day, Remembrance Day and Christmas Day. While employers don't have to pay employees to take a day off, they can't open their shops either. According to provincial law, Victoria Day is among 10 days a year that shops are not allowed to open, with some exceptions.

A monument memorializing Adam Dollard des Ormeaux is located in Lafontaine Park in Montreal. (Gene Arboit/Wikimedia Commons)

21. National Patriots' Day in Quebec

Victoria Day is a federal holiday, which means it must be observed in all provinces, but nowhere in Canada is Victoria Day more complicated than in Quebec. In 2003, the province declared the first Monday before May 25 as National Patriots Day to honour the 1837 rebellion against the British colonial government. It apparently wasn't very popular at the time. Before that, Victoria Day was known in Quebec as "Fete de Dollard des Ormeaux," named after Adam Dollard des Ormeaux, a French soldier who led a military expedition against the Iroquois in Quebec.

22. May "two-four"

Victoria Day is popularly referred to as "May two-four." A two-four is another name for a 24-bottle case of beer. While there seems to be no hard data on the amount of beer consumed from sea to shining sea in Canada, there are anecdotal accounts. Media reports from past years suggest that some Canadian breweries see a 15 to 20 per cent spike in beer sales before the Victoria Day weekend.

23. Campgrounds are dry

Just because it's called "May two-four" doesn't always mean beer is welcome. Many Canadians who seek to rediscover the outdoors by pitching a tent and sleeping under the stars aren't allowed a drop to drink in public parks. Parks Canada and many provincial parks across the country invoke a total alcohol ban during the Victoria Day weekend to cut down on alcohol-related accidents and other booze-fuelled shenanigans. The rules aren't so tight for the rest of year, with most public parks allowing alcohol as long as it stays on your site.

Some breweries have reported sales boosts of 15 to 20 per cent during the May 24 weekend. (Chris Young/The Canadian Press)

24. Long may she reign?

In 2013, a group that included some prominent Canadian actors, writers and politicians called on Prime Minister Stephen Harper to change the name of Victoria Day. Author Margaret Atwood, Green Party leader Elizabeth May and actor Gordon Pinsent are among those behind an online petition to rename the public holiday as "Victoria and First Peoples Day." The petitioners said the new name would give Canadians a chance to honour both the Crown and the indigenous peoples of Canada. The name never changed, and the petition reportedly only ever gathered about 1,500 signatures.