Train passengers are being warned of severe disruption as industrial action continues to affect the region's train services.
A very limited service will run on the following Great Western Railway (GWR) routes, and only until 18:30:
London Paddington to Bristol Temple Meads
London Paddington to Cardiff Central
London Paddington to Didcot Parkway
Reading to Didcot Parkway
Windsor, Marlow, and Henley-on-Thames branch lines
Reading to Basingstoke
Cardiff Central to Bath
No trains will run on other GWR lines, and the only South Western Railway (SWR) services running are between London Waterloo, Hounslow and Basingstoke.
Companies are warning that the trains that are running will be extremely busy. Tickets valid for 7 and 8 October will be valid on 9, 10 and 11 October.
Tomorrow (Sunday 9 October) GWR and SWR trains will start later than usual with some morning services cancelled.
The RMT union, which represents rail workers including guards and signalling staff, is holding the latest in a series of strikes, until midnight.
It is in dispute with the government and rail companies about pay, job cuts and changes to terms and conditions.
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