The tower's exterior was designed by Kohn Pedersen Fox to evoke the graceful curves of traditional Korean ceramics. Pale-colored glass panels, accented with metal filigree, catch light in ways that shift with the weather and time of day. The effect is less steel-and-glass skyscraper than luminous porcelain vessel scaled to the sky. The diagrid lantern-shaped roof structure, completed in March 2016, rises 120 meters alone and covers floors 107 through 123. It was assembled from approximately 3,000 tons of steel parts, each segment 12 meters long and weighing 20 tons, aligned using GPS systems and a 64-ton tower crane. The roof supports its own weight without reinforcing pillars, engineered to withstand earthquakes up to magnitude 9 on the Richter scale.

Seoul Sky, the observation complex occupying the tower's top seven floors, puts visitors nearly half a kilometer above street level. Floor 118 features a glass floor that, at the time of the tower's completion, was the highest glass-floor observatory in the world. The 123 Lounge on the top floor offers drinks at 499 meters. But the most striking experience may be the Sky Bridge Tour on the roof at 541 meters, roughly the same height as One World Trade Center in New York City. From that elevation, Seoul's geography becomes legible: the Han River curving through the city, the mountains ringing the basin, and Seokchon Lake directly below, where cherry blossoms draw thousands every spring. Approximately 8.4 million people visit the tower annually.

Below the gleaming exterior, the tower incorporates environmental systems that belie its massive scale. An advanced geothermal heat pump system draws energy from 720 probes sunk 200 meters underground, supplemented by water from the Han River for heating and cooling. Heat-insulating glass with passive shading reduces energy demand, while photovoltaic panels and wind turbines generate supplemental power. Rainwater harvesting further reduces the building's resource footprint. These systems do not make the tower carbon-neutral, but they represent a serious engagement with sustainability at a scale that few supertall buildings attempt. The tower was designed not just to be tall but to be responsible, a distinction its builders clearly wanted the world to notice.

The tower has attracted attention of a less welcome kind. In 2016, while still under construction, two Ukrainian men infiltrated the site despite 400 security agents posted after intelligence that they planned to climb it. One free-soloed the construction crane to the summit. Posters with their photos, declaring them banned, had been plastered around the site. In June 2023, a 24-year-old British man began climbing the tower's exterior without ropes from ground level. Building security spotted him at the 42nd floor. He took a break at the 72nd floor, where police intercepted him at 313 meters above ground using a building maintenance unit. He later said he had been planning the climb for six months. These episodes have made Lotte World Tower an unlikely landmark in the global urban climbing subculture.

The tower has become inseparable from Seoul's identity in ways that transcend its engineering. Cherry blossom festivals around Seokchon Lake draw enormous crowds each spring, with the tower rising as a backdrop. Fireworks festivals launched from its base have become annual traditions, mixing K-pop concerts with pyrotechnic displays. Even professional golf has adopted the silhouette: the trophy for the LPGA Tour's Lotte Championship in Hawaii is modeled after the tower. For Seoul, a city that rebuilt itself from near-total destruction during the Korean War, the Lotte World Tower serves as both landmark and statement. It says something about national ambition, about engineering confidence, and about a city that spent 13 years arguing over whether to build it, then made it among the tallest structures on Earth.