Overrunning engineering works between Welwyn North and Welham means southbound services are unable to call at Welwyn Garden City and Hatfield.
Southbound services that start at Welwyn Garden City are unaffected and will call at Hatfield as normal.
This is expected until 07:00.
Customer advice:
Trains can not call at Welwyn Garden City or Hatfield, in the direction of London, until approximately 06:00. If you are coming from the direction of Stevenage and require one of these stations you should carry on through to Potters Bar and catch one of the return services that will begin running through the station from 05:46 onwards.
Services that start at Welwyn Garden City are not affected and will call at Hatfield as normal.
Planning your journey:
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Can you tell me more about the incident?
Engineering works are taking longer than planned in the Welwyn area, meaning some of the lines are closed. We're working to monitor progress updates and ensure the railway is fully reopened as soon as possible.
Network Rail are responsible for railway engineering works. These are designed to maintain and improve the infrastructure, and this can include the track itself, the signals, or the points at junctions. Staff will also routinely attend to trees and vegetation by the track, station platforms, electrical supplies and many other parts of the railway.
Most engineering works take place overnight or at weekends, keeping disruption to a minimum. In this case, because the works are taking longer than usual to complete, there will need to be some delays and service changes to the daytime train service. This is because we now have much more limited capacity for trains in this area, and the timetable needs to be reduced to prevent congestion.
Check before you travel:
You can check your journey using the National Rail Enquiries real-time Journey Planner.
Compensation:
You may be entitled to compensation if you experience a delay in completing your journey today. Please keep your train ticket and make a note of your journey, as both will be required to support any claim.