Look up. Look way up — 553.33 metres up to be exact, the crown jewel of Toronto's skyline: the CN Tower.

For a while there, it was the world's tallest freestanding structure and tallest tower.

Bartlett snapped this view of the tower from the Bathurst Street bridge overlooking the CN tracks. (Cameron Bartlett)

Although the official opening was on Oct. 1, 1976, the CN Tower opened to the general public a few months earlier, on June 26.

This Sunday it turns 40, celebrating more than a million and a half international visitors who have come to gaze in awe at the concrete and steel needle in the sky.

People have used the famous venue for anniversaries, birthday parties and marriage proposals.

It's also proved to have an enduring appeal for shutterbugs. Toronto's street photographers case out the city for different angles and perspectives of the tower, hoping to get the perfect shot.

We talked to two such photographers about why they keep on pointing their lenses at the CN Tower.

Cameron Bartlett: freelance photographer, age 26

Bartlett has travelled the world with his camera and has photographed the CN Tower countless times. (David Donnelly/CBC)

On Instagram, his personal account is snappedbycam but he also created postcardsfromthe6 to showcase the work of Toronto's photographers.

Cameron Bartlett is a late bloomer, becoming a serious photographer only two years ago. He dropped out of a digital photography program after only one term, because he quickly realized he was far ahead of the class.

Photography is not only his passion, but his bread and butter, after he became a full-time freelancer about a year ago.

"When I first started it was pretty sparse," he told CBC News one evening, as he waited on the Bathurst Street bridge for the golden hour, that short window of opportunity when the soft light of the setting sun become magical.

"But I feel with the way social media is, and everybody has Instagram, everybody just wants to pick up a camera and kind of join the movement and show Toronto from their own eyes."

Passersby take in a view of the CN Tower from between the Canadian Broadcasting Centre and the Ritz-Carlton Hotel. The CN Tower opened to the public on June 26, 1976. (Kas Roussy/CBC)

'Most iconic building'

"It's obviously the most iconic building," he says. "Wherever you are in the city, it's there, so you can shoot it from a lot of different perspectives. It's definitely one of my favourite things to shoot in the city, for sure."

Toronto's never-ending construction is also something to consider, when you're looking for new ways to shoot the tower. "There's always going to be a new angle, with the city developing and a lot of the architecture that's coming up.

"So it's always going to be kind of refreshing," says Bartlett.

Bora: Urban cityscape photographer, 30-something

Toronto photographer Bora takes a picture of the CN Tower. It crowns the city skyline, he says. (David Donnelly/CBC)

On Instagram, his account is simply bora.vs.bora

"I feel that a bit of mystery actually sweetens the content track that I produce on Instagram," says Bora, standing on the rooftop of a 15-storey apartment building in downtown Toronto.

Bora captures a moody moment from the rooftop of a 15-storey apartment building. (Bora)

Bora picked up his first camera three years ago. Now, his Canon never leaves his side. His photos of the CN Tower figure prominently in his Instagram feed, around 70 times last year, he says.

'It put Toronto on the map'

"Drake specifically has made that a very visible object," he says, referring to the Toronto rapper's latest cover album art where he's perched on the CN Tower.

The cover of Drake's latest album, Views, features the rapper perched on the CN Tower. (Republic Records)

"For me, it's something that uniquely identifies our skyline worldwide. When you see it, in a split second, you know what city it is. It put Toronto on the map."

Bora says he finds unique shooting spots of the CN Tower through word of mouth. He manipulates the photos to create what he calls a fantasy style.

There is no mistaking Toronto's skyline, thanks to the CN Tower. (Bora)

As for Toronto's famous tower, "it does crown the city," says Bora. "It's the pride and joy of the city that stands taller than anything else within our skyline."

Bartlett agrees: "When you go to other cities, and you come back, you realize how beautiful it really is."

Want to see more photos of the CN Tower? Go to streetsoftoronto on Instagram.