Plans to build a £500m rail tunnel from Slough to Heathrow airport have been put on public display.
If it is approved, the tunnel will take five years to build and is predicted to give an £800m economic boost to the local area.
Currently, passengers from the Thames Valley and Wales have to travel to London Paddington and get a connecting train to the airport.
Network Rail proposed building a 3.4 mile (5.5km) tunnel in 2012.
The tunnel, which would start at Langley, will connect to Heathrow Terminal 5 and would mean that journeys from Slough to the airport would be reduced to seven minutes and journeys from Reading will take 26 minutes.
Currently, bus services are the most direct route to Heathrow.
The tunnel would be part a range of upgrade measures on the Great Western Main Line - currently including the £850m redevelopment of Reading Station - which links London, Bristol and South Wales.
Network Rail's western route managing director Mark Langman, said: "The Great Western Main Line is undergoing the biggest modernisation programme since the Victorian era and so it's really important that in developing our plans for the Heathrow link, we take this extensive improvement work into account."
The public consultation, which runs until April, is asking businesses and residents to offer their views on the five-year project, which will require extensive site access at a number of sites around Richings Park, Colnbrook and Poyle.
Slough Borough Council's Ruth Bagley, said: "It is vital that the millions of residents and businesses set to benefit from faster journeys to Heathrow have their say on these updated plans."