Construction on the access bridge to Kansai International Airport (KIX) was finished in March 1994 and was opened to traffic in September of the same year. It has a total length of 3,750m and is the longest truss bridge in the world. The bridge supports both road and rail access to the airport.
Kansai International Airport (関西国際空港) was built on a man made island in the Gulf of Osaka, off the coast of Senshu. It sits about 5 kilometers from shore. The only access to KIX is via the Sky Gate Bridge R. One end of the bridge lies in the Rinku area of Izumisano City in Osaka, the other, Kansai International Airport. Construction on the bridge began in June of 1987 and was completed in March of 1994.
The access bridge is multi-leveled; the upper-level is a 6 lane road, the lower level is a 2 track railway. Electricity, gas, water service, telephone and all others utilities in the airport cross the bridge. The bridge was given the name “Sky Gate Bridge R”, the R comes from the first letter of the words Road, Railway and Rinku.
Generally, a bridge more than 3 kilometers in length is a suspension bridge. It needs supporting beams several hundred meters high, but around an airport, supporting beams of such height can not be built because of the arriving and departing airplanes. The solution was building a truss bridge, which does not need high supporting beams.
(Note) truss bridge: a bridge constructed using the truss structure (girders joined in the shape of triangles).