 This include jet routes, area navigation routes (RNAV), and arrival and departure route.Routes may be defined with a designator; a path to and from significant points; distance between significant points; reporting requirements; and the lowest safe altitude.Recently European ATS service providers are facing a greater change on the European market, with the introduction of Single European Sky, that divides Europe into "functional airspace blocks" – which is replacing the old, national airspace blocks.