Millions of rail passengers face record amounts of disruption as 11,000 rail engineers spend the festive period working to improve rail lines in the region.
For some, buses will replace trains, others will see fewer trains or face longer journey times.
Many of the projects are aimed at helping the overcrowding crisis which is worst on routes into Paddington, London Bridge and Waterloo.
The hotspots will be:
Reading, where a £45 million viaduct to ease congestion will be completed.
Sussex, Surrey and Kent will all be hit by platform closures at London Bridge with some of the biggest alternations to services ever seen. 750,000 journeys a day will be impacted. Part of £6.5 billion Thameslink scheme.
West Coast mainline through Bucks will be badly affected with a closure at Watford.
Most SWT services will be hit by the first of seven weekend closures at Wimbledon. This will affect most services from the region to Waterloo.
Hundreds of thousands of rail passengers are being warned to expect major disruption over the Christmas holiday with a record amount of engineering work scheduled to take place across the region. Our transport correspondent, Mike Pearse, has the details.
Crossrail's new flyover project is one step closer - as the first section of track is laid down.
The 120m Stockley Flyover will provide a vital link for commuters between Heathrow and London.
Services between London Paddington and Heathrow will begin in 2018, with the full route opening in 2019
Once Crossrail is operational, this brand new structure will enable us to increase the number of rail services between central London and Heathrow airport. After four years of planning is it great to see this new infrastructure being brought into service, well done to everyone involved."
Rail passengers and staff across Kent are being given the chance to have their say on the way the county's railways are policed.
By completing a short online survey, British Transport Police wants the general public and rail staff to tell them what concerns them most and about travelling or working on trains and Tubes.
Crime on the railway has fallen for the tenth successive year, but anyone who travels by train is invited to tell BTP their views on how trains and stations are policed, and any concerns they have about using rail services, and if they are worried about any particular type of crime.
The work we have done to reduce crime on trains and at stations in the past twelve months has made a significant impact - Operation Magnum, for instance, has helped to bring down theft of passenger property by 17%
"Railway Policing: What matters to you" can be completed here.
Thousands of passengers using South West Trains will now be able to use free WiFi on some of the busiest routes.
It's now available on the Main Line from London Waterloo to Weymouth and Portsmouth and could benefit more than thirty thousand people who travel along the line every weekday.
Leaves on the line, snow - flooding - landslides! We've heard it all before - but, now there's a new weapon which aims to stop delays - and keep our trains running on time.
It's the new £50 million pound 'night train' - now in action - each and every evening - which repairs the track while we're sleeping. Transport correspondent Mike Pearse reports.
It's cost £50m and is one of the longest and most expensive to ever take to the tracks. But a rail engineering train - replacing hundreds of yards of ballast in the south every night - is a major new weapon to keep trains on time.
Back in February, the country's biggest landslip in recent years saw 80 metres of embankment at Botley collapse during torrential rain. It meant misery for the south's commuters with the line between London, Eastleigh, Fareham and Portsmouth disrupted for six weeks.
The engineering train is currently replacing thousands of tonnes of ballast between Basingstoke and Salisbury before moving to other parts of the network.
As Reading railway station has under gone a £900 million redevelopment, it has meant big changes for passengers and the staff who work there.
Sangeeta has been to meet the members of staff who are making it all work, including the resident hawk!
- Matt Parker- Ticket Office Supervisor
- Simon Plummer- Customer Service Helpdesk
- Ali Butt- Train Despatch at Reading Station
- Katrina Kruger- Passenger Ambassador
- Pat Kemp- Longest serving member of staff
- Max Bell- Bird Controller
- Denise- Resident Hawk!
As thousands struggle home tonight on overcrowded trains, many with standing room only, we can reveal a new scheme to improve the lives of commuters. In a major break with the railway class system, work has begun to rip out thousands of first class seats on the busiest trains to ease overcrowding.
The carriages on Great Western are being converted for standard class passengers. Campaigners says it's a major victory for the majority of travellers over the privileged few.
Our Transport Correspondent Mike Pearse has this exclusive report. He spoke to Managing Director of First Great Western Mark Hopwood and Frazer Langford, also from First Great Western.