Installed in September 2009 on both sides of the Banpodaegyo Bridge, over the Han River in Seoul, South Korea, the Moonlight Rainbow Fountain, with a height of 3,707 feet (1,130 m), is considered as the longest bridge fountain in the world.

Built as a girder bridge, the construction of the Banpo Bridge was completed in 1982. Spanning between the Seocho and Yongsan districts and constructed on the top of the Jamsugyo Bridge, the Banpo Bridge is the upper half of a double-deck bridge, the first double deck bridge built in the country. The Jamsu Bridge, the lower level of the double-deck bridge, is designed to submerge during the periods of high rainfall, as the water level of the river rises and the lower deck goes close to the waterline.

The Moonlight Rainbow Fountain was added by the Seoul Metropolitan Government much later, on both sides of Banpo Bridge in 2009, along with the 1,140 m stretch of waterway, equipped with 380 jets and a dazzling array of multicolored lights, to make a wonderful show, which is recognized by the Guinness Book of World Records as the longest bridge fountain in the world.

The mechanism of the bridge-fountain includes 38 water pumps and 380 nozzles on either side of the bridge that draw 190 tons of water per minute from the river, 20 meters below the deck and shoots as far as 43 meters horizontally, spraying water into a beautiful show of water, music and lights. The water jets can be moved mechanically to change the direction in time to synchronize with the music, to create spectacular ever-changing displays. As the sky becomes dark in the evening, hundreds of multi-colored lights combine with the swaying water spray to create a mesmeric effect in the atmosphere.

Different programmes are scheduled for the fountain to play different shows during the day and night. The fountain is decorated with leaves of the willow trees during the day, when the shining light of the sun creates beautiful sparkles in the water. However, at night everything changes magically and the place becomes a wonderland. As the sun goes down and the dusk sets in, the multi-coloured lights illuminate the fountain with its dancing, rainbow-coloured jets of water in the air, synchronized with the music.

The Moonlight Rainbow Fountain operates four to six times daily, from April to October. Each show lasts for about 20 minutes. In addition to the alluring fountain, the Banpo Hangang Park includes an outdoor stage, ecological observing site and picnic areas. Every Saturday, from May to October, the Park hosts the ‘Moonlight Square Cultural Weekend’, which features a variety of musical styles including classical music, associated with commentary, a cappella, jazz, brass bands and orchestras.