A major train timetable shakeup is arriving at St Albans City and Watford Junction next week.

Commuters should expect to see new rail routes between Hertfordshire and London from Sunday, May 15.

Govia Thameslink Railway's chief operating officer, who looks after Thameslink trains through St Albans City and Harpenden, said the new timetable is part of their plan to "rebuild" the railway for passengers post-pandemic.

Angie Doll, of GTR, said: "The new timetable from Sunday, May 15 is the starting point for rebuilding our railway, to help our customers get where they want to go while reflecting new travel patterns which have changed significantly, particularly on weekdays.

"Our priority is to support passengers by running reliable services, working closely with our stakeholders to support the economic recovery of both local and regional rail."

According to Thameslink, there will be two extra trains to and from Bedford in each of the peaks, and around twice the number of rush-hour trains between St Albans and the capital.

Two trains per hour are set to run between Luton and Orpington, via St Albans, central London and Catford, during the peak period.

Thameslink is introducing a limited route between Hertfordshire and East Grinstead or Littlehampton, West Sussex.

The new timetable also includes two trains per hour between Luton and Rainham, Kent, four trains per hour between St Albans and Sutton, and a small number of extra trains between Bedford and Three Bridges via St Albans and Gatwick Airport.

Herts Advertiser: There will be more trains between Hertfordshire and stations in south London, such as London Bridge (pictured)There will be more trains between Hertfordshire and stations in south London, such as London Bridge (pictured) (Image: PA Wire/PA Images)

Herts Advertiser: Southern will run hourly trains between Watford Junction and Clapham Junction on weekdaysSouthern will run hourly trains between Watford Junction and Clapham Junction on weekdays (Image: PA Wire/PA Images)

Southern, which is also run by GTR, will run hourly trains between Watford Junction and Clapham Junction on weekdays, with one train per day from Hemel Hempstead to London (departing at 7.31am).

On weekends, the route will extend south from Clapham to East Croydon.

To accommodate the Southern route, which existed before the outbreak of Covid-19 in 2020, London Northwestern Railway will slightly reduce its timetable.

Herts Advertiser: London EustonLondon Euston (Image: Will Durrant)

An LNR spokesperson said: "Unfortunately, LNR services at Watford have been impacted by the Southern timetable change, which reduces platform availability at Watford Junction.

"As a result, our peak additional services between Watford Junction and Euston only (calling at intermediate stations) will no longer be able to run.

"Additional calls will be added in alternative services for Bushey and Harrow and Wealdstone, although there will be a reduction in hourly frequency for these stations for some hours of the day."

Herts Advertiser: The May 15 timetable update will mean more peak-time trains between London and Hertfordshire towns, including Hatfield and StevenageThe May 15 timetable update will mean more peak-time trains between London and Hertfordshire towns, including Hatfield and Stevenage (Image: Will Durrant)

Elsewhere on the network, there are changes to Great Northern routes through Stevenage and Hatfield.

Up to 10 trains per hour are scheduled between Hertfordshire and London Moorgate during the peak.

The stopping service between Cambridge and London King's Cross, through Stevenage and Hatfield, will increase from one to two trains per hour.

Thameslink will run extra trains between Welwyn Garden City and Sevenoaks, Kent, at peak times.

Greater Anglia said it will run two Stansted Express trains per hour, with additional peak-time trains.

Herts Advertiser: Greater Anglia will run a half-hourly Stansted Express service with additional peak-time trainsGreater Anglia will run a half-hourly Stansted Express service with additional peak-time trains (Image: Greater Anglia)