The UK's Great Western mainline running from London to Bristol is set to be electrified to improve operations and reduce the network's carbon footprint.
The Department for Transport (DfT) and Network Rail, who are developing the plan, hope the electrification will reduce carbon emissions from transport and also improve the time and relaibility of services.
The work involves the installation of hundreds of miles of electric cables and modifications to tunnels, bridges and stations along the line.
The electrification work, whch will be carried out in phases over the next ten years to reduce disruptions, could cost as much as ВЈ380m.
