Sully Island to Lavernock Point, Vale of Glamorgan


Cliffs of Sully Island
Terrace below Lavernock Point

A headland, layered cliffs, level terraces, sand and pebble beaches, and a small, undeveloped tidal island, accessible at low tide
Carpark at the end of Beach Road in Swanbridge, southeast of Sully; CF64 5UG
A loop of about 4 miles, to tour the island and walk east to and from the point
Adjacent coastline
Photo Tour (28 images)
Lavernock Point is probably the easternmost scenic spot on the southern Wales coast, since beyond, the Bristol Channel shoreline is mostly muddy, and bordered either by grassland or developed areas. The point is a cliff-lined headland, where the shoreline bends by 90 degrees, and at low tide it stands above a band of layered rocks overlain by pebbles that extends up to 800 feet out to sea. To the north are more rocks, smaller cliffs and a few sandy areas, continuing to Penarth, while to the west the coast has a similar mix of cliffs, terraces, pebbles and sand, stretching two miles to Swanbridge Bay and the privately owned but publically accessible Sully Island.

Sully is a tidal island, reachable for several hours around low tide by walking over a natural rock causeway for a distance of a quarter of a mile. The island was the site of an Iron Age fort but little trace of this remains today, and the place presents an entirely natural and undisturbed appearance. On the far side are vertical, reddish-brown cliffs up to 40 feet tall, and all the shore is lined with jumbled, sometimes richly coloured rocks. The coast further west is not so interesting as it generally lacks cliffs or sandy beaches, and the mainland remains relatively built up until beyond Barry, though this section (Sully Bay to Bendrick Rocks) does have some small-scale red rock formations.

The most scenic areas around Swanbridge are the island and the rocks beneath the point, and both these locations can be visited on a loop hike of 4 miles, walking either all along the beaches or partly on the coast path. Parking is available (sometimes free) at the Captain's Wife pub at the end of the dead-end road opposite Sully Island, from where the eastern coast path is along St Mary's Well Bay Road for a mile then through fields and a small nature reserve, bypassing two holiday villages, and along another road to a small inlet named The Cove, just north of the point. Along this 2 mile stretch the cliffs allow access to the beach at just two places, one along a short track to an abandoned house after half a mile, the other on the far side of the first holiday park. The loop hike, therefore, can involve either of these connections, or the beach and/or the path.

Sully Island

A few instances in recent years of people becoming stranded by the incoming tide on Sully Island have led to the installation of a digital warning system at the start of the causeway, displaying the remaining amount of safe time before starting a walk; the danger is in part due to the very high tides in the Bristol Channel, with around a 40 foot vertical difference from low to high. The walk is over flat exposures of sandstone and siltstone from the late Triassic period, alongside a fault line where the rocks drop off up to six feet to the east, to the bushy, grassy land on the north side of the island. A path leads around the perimeter, and above the cliffs on the far side to the high point of 60 feet, overlooking the prettiest section of the shore, where the cliffs rise above little gulleys and piles of rocks. The island is home to a few rare plant species including bee orchid and adder's tongue fern, and has in the past supported a large rabbit population though this was wiped out by myxomatosis in the 1950s. The island is protected as a Site of Special Scientific Interest because of the geology and plant life, and on account of the birds who find sanctuary here.

St Mary's Well Bay and Lavernock Point

East of Sully Island, the inter-tidal zone is formed of rocks and mud, not so photogenic, and a little difficult to walk over, so the easiest option is to stay on the road until the short track that descends a wooded slope to the ruined house (Rock Cottage), at the edge of St Mary's Well Bay; the path emerges from the trees opposite a reddish outcrop named Ball Rock. The bay is partly sandy and partly muddy, crossed by curving lines of tilted strata, and on the far side are larger sandy areas, especially at low tide, when a sizeable sandy ridge is exposed, beyond the furthest rocks. The coast path once ran right above the beach, past another entry point, but this whole section is now closed due to erosion; the next official access is on the far side of the caravan park, down a gap in some low cliffs, beside a tiny drainage. East of here the cliffs rise somewhat higher, up to 130 feet, formed of many thin layers of the blue lias formation, coloured grey/blue to brown, rocks which are exposed in many places further west along the Vale of Glamorgan coast and reappear in this location for just a short (one mile) stretch. Below the cliffs are extensive flat terraces, smooth and split by parallel joints, and these continue round Lavernock Point and a short distance north, where the blue lias gives way to reddish layers of softer, more homogenous marls.

Curving terraces of blue lias
Curving terraces of blue lias, east of St Mary's Well Bay