It connects the business district of La Défense, at Nanterre (Hauts-de-Seine), to Orgeval (Yvelines) where it joins the A13.

The mayor of Montesson had placed a condition on approval of the project that the exit may be constructed if a dual-carriageway relieving the RD121 is also built.

On June 19, 2024, the A14 became the first to utilize automated number plate recognition to determine the vehicle type and distance travelled to calculate the fee, thereby eliminating the requirement for toll booths.

Shortly after this onramp, the A14 turns east then northeast passing through the southern end of the Foret Domaniale St-Germain-en-Laye as a tunnel.

It exits the tunnel and forest near La Grille Royale and crosses the Seine river as the Viaduc Autoroutier de Montesson.

Shortly after that exit, the A14 enters the Nanterre-La Defense tunnel heading east through Nanterre passing under the A86 interchange.