The South Wales Main Line from Bristol Parkway to Swansea is a 61mile (91km) route which would provide a wide range of services including both diesel and electric services, the time period it should be set in would be 2019 when GWR were in the transition phase of retiring the Class 43 from Paddington services and replacing them with the Class 800 having both run on the lines, the route would feature both high speed and local commuter services operated by Great Western Railway and Transport For Wales and would feature the 4 mile Severn tunnel (the border between Wales and England) between Bristol and Newport. The line would feature 19 stations including Cardiff Central, Port Talbot Parkway, Swansea and Bristol Parkway. and for much of the journey would follow the M4 motorway and pass over such landmarks like the Landore Viaduct over the river Tawe. The line is electrified as far as Cardiff meaning services that continue to Swansea need to change power mode. The route could also include the 5mile (9km) route from Patchway to Bristol TM. services are listed as bellow, some services would share the same stops, these will be divided with / (I may have missed some services) SERVICES GREAT WESTERN RAILWAY London Paddington-Cardiff Central: via Bristol Parkway-Newport Class 43 Class 800 London Paddington-Swansea: via Bristol Parkway-Newport-Cardiff Central-Bridgend-Port Talbot Parkway-Neath Class 43 Class 800 Cardiff Central-Portsmouth Harbour via Newport-Severn Tunnel Junction-Flinton Abbey Wood-Bristol Temple Meads/continues on to Bath Class 150/158/166 Cardiff Central-Taunton via Newport-Severn Tunnel Junction-Pilning-Patchway-Bristol Temple Meads/continues to Parson Street Class 158 Great Malvern-Westbury/Gloucester to Weymouth via Bristol Parkway-Flinton Abbey Wood-Stapleton Road-Lawrence Hill-Bristol Temple Meads/continues to Keynsham Class 158/166 Bristol Temple Meads to Severn Beach via Lawrence Hill-Stapleton Road/continues to Montpellier Class 166 Brighton to Great Malvern via Bristol Temple Meads-Flinton Abbey Wood-Bristol Parkway Class 158 Transport For Wales North Wales-South Wales (Holyhead-Cardiff) via Cardiff Central-Newport/continues to Cwmbran Class 175 Marches Line/Swanline via Cardiff Central-Pontyclun-Llanharan-Pencoed-Bridgend-Pyle-Port Talbot Parkway-Baglan-Briton Ferry-Neath-Skewen-Llansamlet-Swansea/Marches Line continues to Gowerton Class 150/175 Freight the line also sees a significant number of freight services to and from the Port Talbot and Llanwern steelworks, this can allow the introduction of the Class 66 Rolling Stock GWR Class 43 (layered if you own Great Western Express) Class 800 Class 150 Class 158 Class 166 (Layered if you own Great Western Express) TfW Class 150 Class 175 EWS Class 66 (Layered if you own East Coastway) Images can be found here: https://imgur.com/a/IaYQ6yc
