There is major disruption on train services due to a landslip at Ockley, near Dorking and over-running engineering works between Gatwick and Victoria.
This means that while major improvement work is carried out on the Brighton mainline there is no direct route available between London Victoria and Gatwick Airport.
Southern is continuing to operate train services from London Victoria to East Grinstead with onward bus connections to the airport and to Three Bridges for those travelling to and from the coast.
A spokesman for Southern said: “Network Rail has been assessing the landslip damage at Ockley and unfortunately there needs to be a significant amount of work carried out to get the track back to normal.
“This will not be a quick repair and we are working with Network Rail to determine what service we can provide in the meantime.
“Instead, we will operate a service between London Victoria and Dorking with onward bus connections to Three Bridges.”
Also today, December 30, there is an hourly bus service between Dorking and Horsham for passengers requiring intermediate stations.
This service is not for customers wishing to travel to London.
Improvement works on the Brighton mainline are taking place between Redhill and Purley and at Gatwick Airport and London Victoria.
The work between Redhill and Purley has closed all lines from Christmas Day to New Years Day and is to replace a major rail junction just south of Purley. This new junction will improve train performance in this area which has suffered from speed restrictions over recent years.
The work at Gatwick Airport is to complete a new Platform 7, along with associated changes to track and signalling in the area. Platform 7 will be used from February 2014. These extra platforms will improve train service performance, particularly during peak times.