(CNN) — The Space Needle, a defining landmark of Seattle's skyline since 1962, has been undergoing a $100 million renovation.

On August 3, it unveiled its latest addition: the world's first and only revolving glass floor, known as "The Loupe."

Standing 500 feet -- or 50 stories -- above street level, the observation deck's new see-through floor offers 360-degree views over the largest city in the Pacific Northwest of the United States

The floor is powered by 12 motors and, as reassurance to the faint-hearted, is constructed of 10 layers of tightly bonded glass.

More than a million guests already pass through the Space Needle annually, with the new attraction sure to bring in a fresh rush of thrill-seekers.

Fifty-six years after the Needle was built for the 1962 World Fair, the futuristic structure's even more futuristic facelift is taking place under the guidance of Olson Kundig -- with the original architect's blessing.

Walls, barriers and entire floors have been replaced by clear structural glass to expand views.</s>Seattle’s landmark skyscraper is set to unveil the world’s first ever revolving glass floor.

The Space Needle, the 605ft high observation tower, will allow visitors on Friday to test their tolerance of heights and feel like they’re literally walking on air.

The rotating glass floor, which is known as ‘the Loupe,’ will be one floor below the Space Needle’s traditional outdoor observation deck.

Richard Green, who designed the rotating glass floor attraction, says visitors will have nothing to worry about.

‘This has 10 layers of glass between us and 500 feet down and they are bonded together with a high strength inner layer,’ Green told KIRO-TV.

‘That means that even if we get a crack in one of these pieces, it will still be fine.’

The newly built attraction at the Space Needle is part of a multi-million dollar renovation project that is coinciding with a tourism boom in the Emerald City.

Last month, the family-owned Space Needle unveiled the biggest renovation in its 56-year history, a $100 million investment in a single year of construction that transformed the structure's top viewing level with floor-to-ceiling glass.

Seattle and King County benefited from $7.4billion of spending by a record 40 million visitors last year, a number that has grown annually since the 2008 recession, according to Visit Seattle, a nonprofit advocacy group for the tourism industry.

Dozens of cranes that have become a mainstay of the city's skyline over the past decade aren't just building apartments and offices, but hotels to absorb the flood of arrivals at Seattle Tacoma International Airport.

'The environment is friendly with this type of investment. It wasn't a difficult thing at all to obtain financing,' said Ron Sevart, president and chief executive officer at Space Needle LLC.

'What we like to say is trends last 50 years. What this investment is more about is the next 50 years, and making sure the space needle stays relevant.'

Hyatt Hotels Corp. is building a 1,260 room tower that's set to become the biggest hotel in the Northwest when it opens in the fall.

In 2017, SeaTac Airport bucked the second year of declines in international arrivals to the U.S., posting a 5 percent increase, according to Visit Seattle.

Seattle's Wright family, which built and owns the Space Needle, is also installing glass in the observation deck's rotating floor and remodeling the restaurant in the first phase of the renovation.

Repainting the exterior of the 600-foot structure and replacing its three elevators will follow, according to Karen Olson, chief marketing officer at Space Needle.

The project is being financed with a commercial loan, she said.

'Keeping your product well maintained and "fresh" increases desirability,' said Jeanne Liu, senior vice president of research at Longwoods International USA Inc., a consultancy that compiles tourism industry statistics for Visit Seattle.

'There are a lot of places to visit in this world, and those destinations with a solid tourism infrastructure that is well maintained can use that as a competitive advantage.'</s>Please wait for video to load:

SEATTLE — The Space Needle’s $100 million renovation project is nearly finished. On Thursday, the highly anticipated revolving glass floor called, The Loupe, was unveiled.

The Loupe is the centerpiece of the landmark’s new multi-level experience, which treats guests to breathtaking views of the ground and interworkings of the structure.

But is it safe? You can hopefully be reassured knowing that between the revolving glass floor and its underlying architecture, there are a total of 10 layers of glass and the glass floor was designed for the highest of code requirements for floors, Space Needle officials said.

For floors, code required loads and testing are typically 60 pounds/square foot and 300-pound point loads. The glass floor at the Space Needle was designed for more than 100 pounds/square foot and 600-pound point loads all throughout the floor’s surface. “This would mean that you could invite the entire Seattle Seahawks’ defense and all of the offensives they would face in the course of a season – to take a group photo on the glass floor without breaking a sweat,” Space Needle officials boasted.

Over the past year, the 56-year-old landmark underwent the biggest renovation in its history infusing the Space Needle’s top viewing levels with glass.

The Space Needle is privately owned and private funds paid for the renovation.

Seattle and King County benefited from $7.4 billion of spending by a record 40 million visitors last year, a number that has grown annually since the 2008 recession, according to Visit Seattle, a nonprofit advocacy group for the tourism industry.

The public can check out the Loupe beginning Friday, August 3 starting at 8 a.m. Adult tickets cost $29/$24 after 6 p.m. kid tickets cost $19/$14 after 6 p.m.

Advance tickets can be purchased online at www.spaceneedle.com or in person at the box office.</s>The world’s first and only revolving glass floor is now suspended and spinning – slowly – at the 500-foot level of Seattle’s iconic, 605-foot-tall space-age inspired Space Needle.

Dubbed “The Loupe” (a reference to the magnifying devices jewelers and watchmakers use), the Space Needle’s rotating glass floor is located just below the open-air observation deck and replaces the original (non-glass) revolving floor that was a feature of the Space Needle’s restaurant when it first opened at the 1962 Seattle World’s Fair.

Visitors can walk, stand, sit or stretch out on the new floor and look down on the Space Needle’s architecture, the elevators and the elevator counterweights, the Seattle Center campus (an urban park with several museums and other attractions) and the city.

The mechanics of the rotating glass floor – or turntable – are also visible and include four motors and 48 rollers that can complete a rotation in varying lengths of time, from a quick 20 minutes to a glacial 90 minutes in either a clockwise or counter-clockwise direction.

“The original revolving floor in the restaurant went clockwise for one rotation in 47 minutes,” said Karen Olson, chief marketing officer for the Space Needle, “So we’re going to start this with one clockwise rotation every 45 minutes and see if we need to adjust it from there.”

In May, the Space Needle marked another milestone in its $100 million makeover, with the unveiling of the first batch of specially slanted clear glass benches on the outdoor Observation Deck at the 520-foot level.

Now all 24 benches, dubbed “Skyrisers,” are attached to some of the viewing deck’s newly installed 11-foot-tall glass windows and invite visitors to lean back and snap selfies that will make them appear to be floating out over the landscape.

Over the past year, while the Observation Deck remained open to the public, construction workers replaced the view-obstructing but structurally necessary half-wall and caging installed when the 605-foot-tall Space Needle was built — in just 400 days — as a centerpiece for the World’s Fair held in Seattle in 1962.

“We needed to update some of the aging mechanical and electrical systems in this 56-year-old building originally designed to look like a flying saucer on a stick,” said Olson, “And we figured, while we’re up there, let’s update the experience and expand the view.”

Seattle-based design firm Olson Kundig, the project architect, maintained the landmarked features of the building while significantly opening up the Observation Deck view with 48 floor-to-ceiling glass windows that are each 7 feet wide and 11 feet high.

The group also added direct viewing lines to the outside for everyone who steps off the elevator, a state-of-the art ADA lift that (finally) makes the outdoor deck fully accessible, an indoor café and the newly unveiled inclined glass “Skyrisers” that will make a trip to the top of the Space Needle super selfie-worthy.

More on the world’s first rotating glass floor

When the Space Needle opened at the Seattle World’s Fair in 1962, it featured a rotating restaurant on the 500-foot level, just below the Observation Deck, that operated on a turntable powered first by a 1-horsepower and, later, a 1.5-horsepower motor. (While novel, it wasn’t the world’s first rotating restaurant. That honor goes to a restaurant that operated in the Ala Moana shopping mall in Hawaii.)

Over the years there have been three different restaurant concepts in the rotating space and this fall plans for the fourth restaurant will be announced. For now, there’s a wine bar.

Inspired by the (non-rotating) glass floor the Eiffel Tower opened in 2014 on its first floor, 187 feet above the ground, and by the glass floors at Chicago’s Willis Tower and the Grand Canyon Skywalk, the rotating glass floor at the Space Needle offers visitors a view down at the fountain, the green spaces and museums on the 74-acre Seattle Center grounds.

Admission to the Space Needle’s upper and lower observation decks ranges by time day from $27.50 to $37.50 for adults, with discounts for seniors and kids.

Discounted admission may be available with bundled attraction passes or some auto club and other organization memberships.

When to go: More than 1.3 million people visit the Space Needle each year, and lines can be especially long during the busy summer tourist season. Consider purchasing a timed-entry ticket online and visiting first thing in the morning (the Observation Deck opens at 9 a.m. Monday to Thursday, and at 8 a.m. Friday through Sunday) or at the end of the evening; closing time is 9 p.m. Monday to Thursday, and 12 a.m. Friday to Sunday, with the last entry 30 minutes prior to closing.

To get a unique view of the iconic 650-foot-tall Space Needle, plan a visit to the Sky View Observatory on the 73rd floor of the Columbia Tower in downtown Seattle. At nearly 1,000 feet, the observatory is the tallest public viewing area in the Pacific Northwest.</s>The Space Needle, a defining landmark of Seattle's skyline since 1962, has been undergoing a $100 million renovation.

On August 3, it unveiled its latest addition: the world's first and only revolving glass floor, known as "The Loupe."

The floor is powered by 12 motors and, as reassurance to the faint-hearted, is constructed of 10 layers of tightly bonded glass.

More than a million guests already pass through the Space Needle annually, with the new attraction sure to bring in a fresh rush of thrill-seekers.

Fifty-six years after the Needle was built for the 1962 World Fair, the futuristic structure's even more futuristic facelift is taking place under the guidance of Olson Kundig -- with the original architect's blessing.

Walls, barriers and entire floors have been replaced by clear structural glass to expand views.

The floor of the rotating restaurant SkyCity is set to become glass as well, and is set to reopen in 2018.</s>The Space Needle unveiled another part of their $100 million renovation on Thursday. Located 500 feet above Seattle, “The Loupe” features floor-to-ceiling glass and is the world’s first and only revolving glass floor.

Visitors that step out onto The Loupe can see the Space Needle’s elevators and counterweights in motion and the city’s surrounding beauty.

Opening day for the public is Friday, August 3 at 8 a.m. Tickets can be purchased online or at Space Needle the box office.

Another new part of the Space Needle are 10 glass benches called “Skyrisers.” The benches allow visitors a chance to take a photo that makes it seem as though they are floating 520 feet above the Seattle skyline.

WATCH: Space Needle's 'Skyrisers' to add to new experience

A new dining experience will be announced in late 2018.</s>Before the Space Needle was ever built, it was a figment of the imagination of Edward Carlson.

Carlson, a Seattle hotel executive who was in charge of planning for the 1962 World’s Fair, visited Stuttgart, Germany in 1959.

It was there that he took a glimpse at a broadcast tower that included a restaurant.

With the World’s Fair scheduled to take place in Seattle just three years later, Carlson wanted to come up with an innovation that would amaze visitors.

The tower in Stuttgart inspired Carlson to take a napkin and begin sketching a tower with an observation floor near its summit.

There were many twists and turns needed to be taken for Carlson’s vision to become a reality.

Planners needed to first acquire a plot of land on the fairgrounds. They then needed to secure private financing.

When a suitable plot of land was found and bought by investors for $75,000 in 1961, builders could get to work on the tower itself.

The Howard S. Wright Construction Company blasted a hole 30feet deep and 120feet across. It was there that the tower’s foundation would be placed.

Eight months later, the basic Space Needle tower was finished.

It officially opened its doors on April 21, 1962 - which was also the first day of the World’s Fair.

The tower, which became a symbol of Seattle, was visited by celebrities including Elvis Presley, the Shah and Empress of Iran, Prince Philip of Great Britain, Bobby Kennedy, John Wayne, Bob Hope, and Walter Cronkite.</s></s></s>
The Space Needle in Seattle unveils the world's first revolving glass floor.