Train services have resumed between London Bridge and East Croydon enabling Uckfield trains to get back into action.
Network Rail and Thames Water engineers worked for more than a day to mend a deep hole under the railway between Norwood Junction and New Cross Gate for repairs to be made.
Engineers found the problem section of pipe and had to work to seal it and divert the water. This then allowed Network Rail to begin filling in the hole with layers of concrete and stones.
The railway re-opened this morning after test trains were run overnight to make sure the line was safe for passengers.
Uckfield rail services were severely disrupted after the sink hole was discovered with cancellations and services halted short of their destinations.
A considerable number of people were bussed home from Oxted along country lanes, more than doubling the length of the journey.
• Find Southern’s live running information page here.