The road begins near to the National Stadium of Jamor and sets off in an approximately east-north-easterly direction, intersecting along the way with major regional roads ( IC19, A16, IC22 ) as well as two national motorways, the A8 and the A10.
Despite running for its entire length within 20km of central Lisbon, much of the route of the A9 is semi-urban or rural, incorporating mountainous regions that necessitated the inclusion of 15 viaducts and two substantial tunnels in its construction.