Cost estimates of the options for a realignment of the A27 around the West Sussex town range from £135m to £260m.
Two routes for a byass to the south of the town are proposed. A third option on the table is to widen the A27 in the town on its existing route. Each would create a new dual carriageway to join up the two existing sections of dual-carriageway either side of Arundel.
A public consultation on the proposals starts today and runs until 16th October 2017.
Highways England programme manager Valerie Stephens said: “The single carriageway A27 through Arundel has been a missing link in the road network for decades. Now, major improvements are finally within reach.”
She added: “Arundel has a special environment and a unique cultural heritage and, while building any new road will have an impact, we are committed to delivering the improvements responsibly and have developed our proposals with the environment very much in mind.”
The project is one of three major improvements for the A27 being taken forward by Highways England, including upgrades between Worthing and Lancing and to the east of Lewes.
Details on the proposals and feedback forms are available on the Highways England website until 16th October 2017.