The £160m improvement project set to take place to upgrade the track and points at Clapham Junction over the Easter period.
The work will also see improvements made to the signalling equipment at Clapham Junction with engineers working on the London-Sussex mainline.
By replacing the points at Clapham Network Rail will help to improve the reliability and punctuality of services for passengers.
This follows the recent announcement that digital signalling equipment is set to be tested on the Northern City Line.
The resignalling scheme is set to be complete by Christmas this year and will see the current 1970s-era signalling replaced with modern LED signalling.
This resignalling work will also see the installation of new control and train detection systems.
Control will also be relocated to Network Rail’s Three Bridges route operating centre from the original 1970s Victoria control centre.
Network Rail spoke on the work set to take place at Clapham Junction and the benefits it will bring.
Katie Frost, Network Rail’s Route Director for Sussex said: “I realise this stretch of track seems to be closed a lot lately – but there’s a good reason for that.
“Major investment always means there is a degree of disruption while the work is done and we are midway through that process now.
“The equipment we are installing will be more reliable.
“The project will also reduce everyday delays through new designs of track and signalling.”
Following on from the work at Clapham Junction, engineers are also set to work on the new station development at Gatwick.
Rail industry leaders from across the South are set to meet at this years TransCityRail South event to discuss and debate the key rail infrastructure projects taking place in the South, for more information click here.