Cheongna City Tower, Tower Infinity or Ecoprism Tower is a tower to be constructed near the Incheon Airport just outside Seoul, South Korea. The tower is dubbed as the "world's first invisible tower". The invisibility illusion will be achieved with an LED facade system. The tower is built primarily for leisure activities. The building will be spread over an area of 145,500 m2 (1,566,000 sq ft). The Design by GDS got first prize in a National Design Competition sponsored by Korea Land and Housing Corporation. The South Korean government gave approval to build the tower in September 2013.