Kehä III ("ring three", National road 50; or Kantatie 50; Swedish: Ring III or Stamväg 50) is an important highway in Southern Finland. It is the outermost of the three beltways in the Helsinki region, and the first one to be built. It lies across the four Finnish municipalities of Kirkkonummi, Espoo, Vantaa and Helsinki. Shaped like an arch, the road is 46 kilometres (29 mi) long, of which only a very small fraction passes within the borders of Helsinki itself.