9k Run Sully: Scenic Coastal Path from Swanbridge

Route Overview & Local Insights

This 8.5km out-and-back route offers a rugged and rewarding coastal running experience between Swanbridge and Lower Penarth. Starting from the Sully car park, you'll tackle an undulating terrain that balances paved lanes with narrow, technical bare-earth trails. With a modest 86m of ascent, the route is categorised as gently hilly, but the coastal breezes and uneven sections provide a fantastic workout for your stabiliser muscles. Runners will enjoy sweeping views of the Bristol Channel, passing several hidden coves and rocky outcrops that make every kilometer feel distinct and engaging.

Steeped in maritime and scientific history, this stretch of the Vale of Glamorgan coastline is world-renowned for its geological significance. As you run past Lavernock Point, you are passing the very site where Guglielmo Marconi sent the first-ever wireless radio transmission over open sea in 1897. The area is also part of the Glamorgan Heritage Coast, famous for its Jurassic-era cliffs and fossil beds. Keep an eye out for Sully Island at the start of your run; this tidal island was once a notorious stronghold for smugglers and remains a striking local landmark that changes character with every tide.