The tower's original mission was ideological. Completed on December 3, 1971, it was South Korea's first general radio wave tower, designed primarily to block North Korean television and radio signals from reaching Seoul's population. The 236.7-meter structure, sitting atop 243-meter Namsan mountain, gave it an effective elevation of nearly 480 meters above sea level, enough to dominate the broadcast spectrum across the capital region. It still transmits signals for KBS, MBC, SBS, and a roster of FM stations. When the observatory finally opened to the public in October 1980, Seoulites discovered that their functional broadcast infrastructure also happened to offer some of the most spectacular urban views in Asia. The tower quickly became the city's defining landmark, and a 2012 survey by the Seoul Metropolitan Government confirmed what most locals already knew: foreign tourists ranked it the number one attraction in the city.

The love padlocks started quietly and became a phenomenon. Couples began attaching inscribed padlocks to the fences on the rooftop terrace, then throwing away the keys as a symbol of eternal love. By 2011, when the Seoul Metropolitan Government polled nearly 2,000 foreign visitors, 16 percent cited hanging a love lock as their favorite activity in all of Seoul. The tradition echoes the love locks once found on the Pont Neuf in Paris, but the sheer density of padlocks at N Seoul Tower, covering trees, fences, and purpose-built structures, has made it one of the most recognizable expressions of the practice anywhere. Korean television dramas and films have featured the locks repeatedly, reinforcing the tower's identity as a place not just for viewing the city but for marking a relationship within it.

Since its renovation in 2005, the tower has served as an unlikely environmental indicator. On evenings when fine dust concentration in Seoul stays below 45 micrograms per cubic meter, the tower glows blue from sunset to 11 p.m., or 10 p.m. in winter. On poor air-quality days, the blue light stays dark, a visible signal to millions of residents that the air they are breathing is compromised. The lighting system uses LED technology that also supports digital art installations called Reeds of Light and Shower of Light, transforming the tower into a canvas visible across the city. Once a year during Earth Hour, the lights go dark entirely in solidarity with the global energy conservation campaign. The 2005 renovation, which added the N to the tower's name, standing for new, Namsan, and nature, cost a substantial sum and repositioned the structure from functional broadcast equipment to cultural icon.

The Namsan cable car, which carries visitors up the mountainside to the tower's base, is itself one of Seoul's enduring experiences. Approximately 8.4 million people visit N Seoul Tower each year, many of them ascending through the forested slopes of Namsan Park before reaching the plaza. The tower's interior is organized into three sections: N Lobby at the base, N Plaza with restaurants and the padlock terrace, and N Tower with observation decks on floors 4F and 5F and a revolving French restaurant called N Grill on the top floor. In a detail that reveals something about Korean culture, the tower includes a fourth floor despite the widespread practice of tetraphobia, the fear of the number four, in Korean buildings. The designers sidestepped the taboo by appending an F suffix to each floor number. There is, however, no sixth floor, a gap the tower has never bothered to explain.