More details on the construction of the M4 Smart motorways have been released by Highways England.
It is the biggest smart motorway scheme yet and the biggest road scheme under construction in the South East. It'll cost £848m and will see the hard shoulder turned into a fourth lane.
This will span across a 32-mile stretch from Junction 3 near Heathrow to Junction 12 at Theale.
Almost one thousand workers will be based in Reading from January at a site which is the size of 25 football pitches.
The scheme is likely to cause disruption for drivers.
Our Transport Correspondent Mike Pearse spoke to Lynne Stinson from Highways England, Ella Northey and Krishma Kapoor who are apprentices working on the construction of the motorway.