(CNN) — Since its inauguration on October 20, 1973, the iconic Sydney Opera House has been the centerpiece of Sydney Harbour, drawing millions of visitors every year.
From its complicated construction to popular bars and restaurants, this UNESCO World Heritage Site is full of surprises.
Before you visit, find out about its fascinating history and the best things to do:
Creativity and strife
The Sydney Opera House.
Sitting on Bennelong Point in Circular Quay, the Sydney Opera House was always intended to be a national landmark -- as outlined in the international design competition for its creation.
"In the 20th century, Sydney was often described as sort of a 'Manchester by the Sea' for being a bit of a backwater international city," Bruce Barnett, a guide at the Sydney Opera house, tells CNN Travel.
"So it was important that this building represent a new Australia, a very outward looking and progressive country."
Of the 233 entries, a design from relatively unknown Danish architect Utzon captured the imagination of the judges.
Rather than the boxy buildings that were common at the time, Utzon's winning concept featured sinuous curves and a unique silhouette -- a series of vaulted structures that resemble billowing white sails or stacked shells.
Construction of the shell-shaped roof.
J. R. T. Richardson/Hulton Archive/Getty Images
Beautiful as it was, the design proved to be extremely difficult to execute -- nothing like this had been done before.
Instead of the estimated four-year timeline and A$7 million (US$5 million) price tag, the project took 14 years and a whopping A$102 million to complete.
Because of delays, mounting expenses and a souring of relations between Utzon and engineers, Utzon was forced to resign midway through the construction.
“It was described as a building that changed a nation.”
He never returned to Australia to see the completed building in person, though he did won a Pritzker Prize in 2003 in light of his achievements. The architect also developed a conservation plan for the Opera House.
"The building was so important, it was described as a building that changed a nation," says Barnett.
"Suddenly Australia was on the world map. We didn't just eat pies and go to the beach and surf and drink beer -- we had culture too."
Now that you know some background, here are some things to do:
Get tickets to a show
Aussies know the reason to visit Sydney in winter is 'Vivid Sydney,' a spectacular 90-installation light show, music festival and arts showcase.
Despite its name, the building hosts more than 2,000 shows a year and only about 15% of them are opera.
There's standup comedy, indie rock gigs, orchestras, ballet, art and culture lectures, theater, dance and international concerts.
"When we do rock and pop, it tends to be quite indie -- we have carved out a niche for ourselves with that type of music," says Barnett.
"For the international acts, you really have to book far, far ahead."
Go on a backstage tour
An engine room of the Joan Sutherland Theatre inside the Sydney Opera House.
PETER PARKS/AFP/AFP/Getty Images
Once inside, it quickly becomes apparent how massive this space really is. There are six indoor performance venues (plus one more outdoors), more than 1,000 rooms and six restaurants.
In order to enjoy freedom to explore the opera house before rehearsals begin, a 2.5-hour backstage tour takes place every morning at 7 a.m.
“Suddenly Australia was on the world map. We didn't just eat pies ... surf and drink beer -- we had culture too.”
The tour explores the stages, dressing rooms, orchestra pits and rehearsal rooms, offering insights into all the operations critical to bringing the performances to life.
"From the audience's perspective, it's all glamorous with the makeup and costume and props. But from the performance perspective, there's machinery, cables, and motors -- it's highly mechanical backstage."
The morning caps off with an a la carte breakfast in the Green Room -- a space usually reserved for the stars.
Meet the Sydney seal
Not just tourists love to visit the Sydney Opera House.
Throughout the year, a New Zealand fur seal named Benny can be seen playing in the water or basking in the sun along the Northern Broadwalk of the Opera House.
An unofficial mascot, the wild seal comes and goes as it pleases.
In 2016, a second seal -- which is thought to be a pup -- joined Benny in the sun but has yet to be spotted again this year.
View the sunset
Sunset over the opera house.
Sydney Opera House Trust
If you ask most travelers about the color of the opera house, they'd confidently declare it white or beige.
But there are more than 1 million Swedish roof tiles covering the structure -- and they actually change color as the day goes on, mirroring the sky.
In the evening, the opera house transforms, as if absorbing the pinks and oranges of the sky.
"A lot of people think the rooftop is covered in cement and they don't realize that it's actually tiles that are reflective," says Barnett. "It looks almost like it's glowing at night. It's really beautiful."
Enjoy waterfront drinks
Afternoons at the Opera Bar.
For the best sunset views, visitors will want to visit the Opera Bar.
It's a favorite among locals and tourists alike thanks to the waterfront setting, casual atmosphere, charcuterie boards, wine list and live music nearly every night of the week.
"The Opera Bar and Opera Kitchen have become very much a place for Sydneysiders to come after work," says Barnett.
"Weekends you can't move down there, but it's always a great time."
To have your choice of a sunset spot, Barnett suggests arriving before 5 p.m. on weekdays -- that's about the time when people knock off work and head out for a sundowner.
While the bar is best known for its energetic evenings, it's certainly worth a visit for breakfast or brunch.
Dine like the stars
Bennelong's Opera House-inspired meringue.
Built inside one of the sails, the Bennelong fine-dining restaurant takes its name from Woollarawarre Bennelong -- an Aboriginal elder who served as a statesman and translator when the British settled in Australia in the 18th century. The opera house sits on the peninsula where he lived.
The restaurant, helmed by award-winning chef Peter Gilmore, delivers a dramatic atmosphere with rib-like ceilings and excellent harbor views, while it serves up a feast of Australian flavors, from Tasmanian truffles to suckling pig from Macleay Valley, north of Sydney.
Designed to be enjoyed pre- or post- performance, you can enjoy several tasting menus, as well as a la carte dining for those sitting down for a more casual bite.
"Bennelong is all about Australian produce and wine. The menu highlights Australia's best food," says Barnett.
"There's also a fantastic dessert that you have to try -- pavlova done in the shape of the House."
When to go
Inside the Sydney Opera House.
The Sydney Opera House welcomes roughly 1,200 visitors for tours each day -- some independently, others in large group outings.
Barnett suggests visiting early in the morning or late at night to avoid crowds, though most tours are planned to ensure smooth traffic.
"I think that 9 a.m. on a Sunday morning is the best time to go. Generally speaking, we have great access to all the theaters and I think it's a really peaceful time to visit."
Other times -- like school holidays in January, hot summer days or rainy afternoons -- visitors arrive in droves.
"We don't get a lot of rain, but when we do, it's really heavy and bucketing down," says Barnett. "Suddenly you have a rainy afternoon and people are thinking the Opera House would be a wonderful way to spend the day."