Engineering work is taking place between Patchway and Severn Tunnel Junction, closing all lines.
On Tuesday 25 and Wednesday 26 December, no trains will run.
Transport for Wales:
It is not yet known how Transport for Wales will be affected by this engineering work.
CrossCountry:
Thursday 27 to Tuesday 1 January:
Services via Severn Tunnel:
The 05:20 Bristol Temple Meads to Cardiff Central will not run. The 07:00 Cardiff Central to Manchester Piccadilly and the 17:05 Manchester Piccadilly to Cardiff Central services will run between Bristol Temple Meads and Manchester Piccadilly only.
Customers travelling between Cardiff Central and Bristol Temple Meads should use alternative services.
Services via Chepstow and Gloucester:
Services between Cardiff Central and Nottingham will run between Chepstow and Nottingham. Replacement buses will run between Newport and Chepstow.
Great Western Railway:
Buses will replace trains between Newport and Bristol Parkway, with both fast and stopping buses running on this route.
An amended timetable will be in operation between Cardiff Central and Newport, and also between London Paddington and Bristol Parkway. Services that usually run between Cardiff Central and Taunton will run between Bristol Temple Meads and Taunton only. No Great Western Railway services will run to / from Brighton.
Check before you travel:
These changes are not currently shown in the National Rail Enquiries Journey Planner, please check back nearer to the time of travel.
You can find the location of your bus replacement by checking station signs or by searching for your station on our station information pages
Bicycles:
Non folding bicycles are not allowed on rail replacement bus services at any time. Folding bicycles are allowed if fully folded. For more information, please see here.
Project Information:
The Great Western Route Modernisation project is the biggest investment in the Great Western railway since Brunel built it more than 150 years ago. Modernising the route will improve the experience of everyone who uses it and stimulate economic growth in the South West and beyond.
Network Rail are electrifying one of Britain's oldest and busiest railways, providing greener, more reliable journeys and improving connections across southern England and South Wales: London and Bristol, including Cardiff, Newbury and Oxford. This project is also part of the London Railway Upgrade Plan, creating new connections and increasing capacity in peak hour by 30%.