Arun Valley Line Improvement Project

Saturday 14 August - Sunday 22 August 2021

Nine day closure affecting all trains via Horsham

There will also be five weekends of engineering closures in July, September and October.

Don’t get caught out, please check back regularly.

Sammy the seagull on a sign against a blue sky

What is the Arun Valley Line Improvement Project?

We’re investing £750m in the Sussex Upgrade Plan to improve the network for passengers. By replacing ageing infrastructure, we’ll reduce delays and make the railway safer.

As part of the plan, we’re carrying out essential engineering work to make the Arun Valley line safer and more reliable. This will allow for future passenger growth and improve passenger journeys.

What work is taking place?

  • We’re renewing nine sets of switches and crossings, which are the movable sections of track that guide trains from one track to another and allows them to cross paths.
  • We’re also renewing a section of rail, sleepers and ballast, as well as replacing track drainage at Horsham station.
  • These track upgrades will give passengers smoother and more reliable journeys, while the drainage work will help maintain track quality for years to come.

Why are the works going ahead now?

  • The existing equipment, having been in place since the 80s, is outdated and needs to be replaced. The newer and more reliable equipment will reduce faults and delays.

Map and line closure details

Please click to open the map.

Line closures explained

  • All lines via Horsham will be closed.
  • No trains running between Arundel and Dorking & Arundel and Crawley on all affected days
  • Trains between Crawley and Three Bridges will be running on weekdays but closed on all affected weekends
  • Bus replacement services will operate throughout. Check your journey at

Key Dates for your diary

Lines via Horsham will be closed on the following dates in 2021:

July: 11, 17 – 18 and 31
August: 1 and 14 – 22
September: 4 – 5
October: 3

Please check before you travel

Please plan your journey as you may need to allow more time.
Rail replacement bus services will be running during these line closures.
Some train services will be altered or diverted. Check before you travel at

Guidance for passengers on rail replacement bus services

Please wear a face covering and follow the latest government travel advice when using rail replacement bus services.
Please n
ote that non-folding cycles cannot be carried on replacement buses.

Are the buses accessible to disabled or elderly customers? If not, what arrangements are made for customers?

When we provide rail replacement buses or coaches for planned disruption, we use accessible vehicles. In any circumstances when this is not possible, our Assisted Travel and frontline teams will always identify an alternative journey plan to enable you to complete your journey.

If you would like to speak to the assisted travel team about your requirements, please call:
Southern: 0800 138 1016 or 0800 138 1018 (Textphone)
Thameslink: 0800 058 2844 or 0800 138 1018 (Textphone) or visit the Southern or Thameslink accessibility websites for further information.

What is the travel advice?

If you do wish to travel, please note you will need to allow extra time for your journey. Replacement bus services have been arranged but please remember that capacity may be restricted due to the government’s coronavirus travel advice.

How should I check my journey on the day of travel?

Information regarding any on-the-day disruption or unplanned alterations, including real-time travel advice will be available from these websites:

Station car parks

The station car parks at Arundel and Crawley will be closed on all days when rail closures are taking place. This is to allow for the safe operation of rail replacement buses. If you are planning on driving to these stations, you will need to find alternative parking, or you may find it easier to use a different nearby station.

There will also be reduced number of spaces available in the car park at Horsham station during these works. This is to allow engineers space to carry out the track upgrades.

Printable leaflet

Please click here to download and print the leaflet.