TESTS on overhead wires above train tracks in the Reading area will lead to several route changes and diversions this weekend.

This engineering work will affect all Thames Valley and High Speed services, causing confusion and consternation for hundreds of train travellers.

They are being carried out by Network Rail to prepare for new electric Great Western Railway trains which will be running through Reading soon.

On Saturday morning, there will be an hourly train service from Swindon to London Paddington calling at Chippenham and Reading which will add up to 25 minutes to the overall journey.

After midday on Saturday and all day on Sunday, there will be an hourly train service from Swindon to London Paddington which will add up to 70 minutes to the overall journey.

These trains are expected to be extremely busy as they are coming from Swansea.

There will be a separate hourly service to Didcot Parkway for connecting buses to Reading.

Replacement buses between Swindon and Bristol Parkway will not run from 8am on Saturday September 16 until 2am on Monday September 18.

Replacement bus services from Reading to Swindon will be available after 2pm on Saturday and all day on Sunday.

Throughout the weekend, most trains between Swindon and Westbury will be re-timed, with some trains running earlier than usual so passengers should double-check their train times before they head off.

Anyone travelling to London Paddington from Bristol Temple Meads should be aware that after 12.15pm on Saturday and all day on Sunday, there will be an hourly train service to London Paddington calling at Swindon only, adding up to 70 minutes to the overall journey.

On Sunday these trains are expected to be extremely busy as they are coming from Penzance and Plymouth.

For a more comfortable journey from Bristol to London on Sunday, there will be a separate hourly service to Didcot Parkway calling at Bath Spa, Chippenham and Swindon, then travellers should change at Didcot Parkway for a connecting coach service to Maidenhead.

Trains will run regularly from Slough into London Paddington.

Anyone travelling from Bath Spa to London Paddington should know that after 1.30pm on Saturday and all day on Sunday, there will be an hourly train service to London Paddington calling at Chippenham and Swindon only, adding up to 70 minutes to the overall journey.