The Southern Access Road (SAR) will be a new access into Coed Darcy from the south and will run to the east of Pen Isa’r Coed Farm, crossing over Crymlyn Bog, and linking to the Jersey Marine Link Road, allowing access on to Fabian Way. 

The proposed road is described as a "rural road," incorporating a viaduct bridge, allowing the road to cross the operational Swansea Burrows Freight Railway Line and the Tennant Canal. Additionally, the work to set out the road will include an underpass to accommodate an existing track access in the southern area, together with access tracks in the south-west and north-west. An agricultural access adjacent to Pen Isa’r Coed Farm will maintain access either side of the road and allow occasional HGV access to the farm and a gravel access track north-west of the farm to maintain access to the north-west.

The proposals are set to deliver:

• the removal of the old pipe and introduction of the new high viaduct will present less shading and give more potential for habitat improvement in the Bog;
• new routes and views will for pedestrians, cyclists and vehicle users;
• a new route between Neath and Swansea;
• links for cyclists and walkers onto the Celtic Trail;
• severance between the coastal margin and Coed Darcy will be removed;
• excess traffic will not have to pass though the Jersey Marine village or past the school, which will improve safety for local residents;
• an opportunity will be provided to create viewpoints and information boards for the Bog and the Scheduled Ancient Monument, St. Margaret's Chapel.