The three mile stretch of the Bristol Channel shoreline from Aberthaw westwards to Stout Bay forms the easternmost section of the Glamorgan Heritage Coast, which is characterised by straight cliffs of thin-layered blue lias (limestone) above pebble or sand beaches and extensive wave-cut terraces. Around Aberthaw, where the meandering, estuarine mouth of the River Thaw was rerouted to a straight channel to facilitate construction of a coal-fired power station in the 1950s, the coast is bordered by fields and patches of marshy grassland, but the cliffs rise up a short distance west, starting above Summerhouse Bay, continuing round the promontory of Summerhouse Point and on to Stout Bay, the far side of which is formed by Stout Point, a projecting headland passable at beach level for only a couple of hours around low tide. West of here, the cliff and terrace landscape continues another ten miles, to such places as Nash Point, Dunraven Bay and Ogmore-by-Sea.
The eastern Heritage coastline is best accessed near Aberthaw, via a quiet, dead-end road to a free parking area beside the power station, from where the coast path runs westwards over stony grassland, past Limpert Bay and Penry Bay to the start of the cliffs at Summerhouse Bay, where it climbs and follows field margins for 2.5 miles to the next point accessible by road, Cwm Col-Hugh, near Llantwit Major. One other point of interest along the initial stretch is the overgrown earthworks from an Iron Age fort, at the centre of which are the ruins of an 18th-century summer house, from which the adjacent bay is named. The majority of the path gives only fleeting glimpses of the sea, however, since most follows thick hedgerows that obscure the southwards views; instead, like all of the Heritage coast, the scenery is much more interesting below the cliffs, seen by walking along the beaches and terraces.
The first 1.4 miles from Aberthaw are not so scenic, all along the edge of Limpert Bay, where the intertidal zone is mostly covered by large, rounded, shifting pebbles, so the path is perhaps the best option here, but the next part, 1.6 miles to Stout Point, is much more photogenic, and fairly easy to explore, traversing some patches of loose rocks but mostly flat terraces. Other features include tiny caves, at least one arch, several rockfalls and many tidepools.
The approach to the Aberthaw coast is along Gileston Road, south of the B4265 - through a small village and down a lane, ending at the Limpert Bay guesthouse, beside a parking area with an information board about the area and the coast path. A ruined stone cottage adjoins the car park, formerly part of the old farm of Limpert. A narrowing band of undeveloped land stretches westwards, between the beach and fields to the north, and this provides a course for the coast path, which crosses a few minor streams and follows close to a long line of concrete blocks known as the Dragons Teeth, placed here during World War II to guard against tank invasions. Limpert Bay is generally just out of site of the path, hidden by a bank of stones, all rounded, light grey blue lias; a band of these pebbles extends about 100 feet seawards, then beyond, at low tide, are terraces and patches of mud and sand. The bay is also notable as being the southernmost point in Wales.
The surroundings are little changing for over a mile, as the grassy land gives way to a crop field, now bordering the similar-looking Penry Bay. On the far side of the field, the path briefly follows the top of a stone bank, past the edge of a house and garden, then starts to climb as the cliffs form, rising steadily above Summerhouse Bay. The cliffs are composed of the same blue lias exposed on the beaches but the land hereabouts is higher due to geological folding. For 800 feet the path passes through a patch of overgrown woodland at the edge of the ancient hillfort, the site of which is mostly covered by the vegetation, though the area is crossed by a couple of paths, and traces of ridges and ditches can just be discerned. The undergrowth also largely hides the more recent structure, an octagonal tower enclosed by low walls incorporating several smaller rooms, remains of a summer house built here at the end of the 18th century. After passing the fort, the path emerges to one corner of a large field, location of a coast guard lookout station, then ahead the surroundings are little changing for 2.5 miles, past Stout Point to the beach at Cwm Col-Hugh.
Walking westwards from Summerhouse Bay, the cliffs are seen to rise over a short distance, and are soon 130 feet high; they are composed of many thin layers of greyish brown limestone separated by softer, dark grey shale, while below are nearly flat terraces, slightly inclined and eroded at intervals to form low, gently curving ridges, initially angled approximately perpendicular to the cliffs. Along the lower portion are a few tiny caves and angular crevices, though most of the cliffs are straight and rather featureless. A longer section of the coast comes into view once around the minor promontory of Summerhouse Point, extending another mile to Stout Point, with the lighthouses of Nash Point visible beyond. The cliffs become higher still and there are several large piles of fallen rocks along the base, while the neighbouring terraces are for some distance mostly covered by pebbles and boulders, though the flat strata reappear towards the far end of this section of the coast, at Stout Bay. Here, the low ridges are more curved, and at low tide they are separated by some lengthy pools, reflecting the adjacent cliffs. The exposed, dark grey rocks are covered by barnacles and reddish seaweed (corallina officinalis).