The 123F Lounge in the Lotte World Tower in Seoul.

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Seoul, South Korea CNN  — 

The journey to the highest restaurant in South Korea starts with a whale display.

The airy 123F Lounge sits on the top floor of the Lotte World Tower in Seoul, 555 meters (about 1,820 feet) above ground. The tower is the tallest building in the country – and the fifth tallest building in the world, according to its official site.

But it turns out, getting to the restaurant isn’t as straightforward as hopping on and off an elevator; it’s a whole experience that can easily take up to an hour.

After buying an entry ticket – 27,000 Korean won (roughly $20) for adults, and 24,000 won ($18) for children – visitors enter a waiting hall, awash in blue light as whales swim across a giant screen on the ceiling.

Several different rooms follow – some with opportunities for professional photos, others displaying the building materials that make up the tower – before a puzzling series of whale-themed spaces.

A temporary exhibit showcasing whale-themed multimedia displays in the Lotte World Tower in Seoul, South Korea.

There are two long hallways – one illuminated dark blue as whales swim beside you on wall-length screens, the other with LED ceiling panels rotating through colorful mosaic patterns, in sharp contrast with black-and-white whale photos on the wall. Vaguely whale-sounding calls add to the underwater ambiance. Another room has fake clouds suspended midair and whales painted on the wall, appearing mid-flight.

(I later learn this is all part of a temporary exhibition celebrating the work of whale photographer Jang Nam-won.)

Many whales later, you finally reach the elevator, which takes a minute to travel up to the Seoul Sky observatory, traveling at 10 meters per second.

Sunset from the Sky Seoul observatory, located in the Lotte World Tower.

Stepping out, visitors are guided to sit in a dark room as a video, apparently an artistic rendering of the history of Seoul and the Lotte World Tower, plays – before the screen splits into two giant panels, slowly lifting like a curtain to reveal the breathtaking view of Seoul through floor-to-ceiling windows.

The observatory spans multiple floors, with giant windows that allow a sweeping 360-degree view of the metropolis. One can spot the iconic N Seoul Tower perched on Namsan mountain, bridges stretching across the river, parks and sports stadiums and even the rides at the nearby Lotte World theme park.

Each floor offers different attractions, such as small cafes on the 119th and 122th floors. There’s the Sky Deck on the 118th floor, with a glass floor that lets you see all 478 meters (1,568 feet) between your shoes and the street far below. There’s the Sky Terrace on the 120th floor, an outdoor balcony with a perfect view of the winding Han River.

The Sky Deck on the 118th floor of Seoul Sky, with a glass floor.

After the appropriate amount of ooh-ing and aah-ing, you finally reach the lounge on the 123rd floor.

The restaurant is both spacious and cozy, with cushy chairs and lamps on each table. Windows make up an entire wall, stretching up to the high ceiling to flood the space with warm light during sunset. A free viewfinder allows you to zoom in on the landscape.

The menu is on the pricey side by Korean standards – $28 for a beef stew, $19 for tomato spaghetti and $18 for a Caesar salad – but we took our time, watching the sun dip beneath the horizon, briefly turning the sky fiery orange.

The restaurant also offers pizza, sandwiches, steak and appetizers including a cheese selection.

Window seats at the 123F Lounge boast sweeping views of the Han River in Seoul.

The view was just as stunning in the dark, the city a grid of light spread out before us.

Though the 123F Lounge is a perfect spot for a romantic dinner or special date, there were also families with children and young adult friend groups when we visited. The lounge can also be rented for special events such as wedding receptions and product launches.

The Lotte World Tower is located in the Jamsil neighborhood of Seoul’s southeastern Songpa-gu district. It’s open all week, though hours depend on the day, and is accessible by subway, bus or private vehicle.