Towards Talyllyn, the sky above the Dysynni Valley is squeezed by the summits and slopes of the southern Snowdonia Mountains.
Here at its source, the River Dysynni seeps from the lake and creeps past Craig-yr-Aderyn- Bird Rock- home to choughs and the only inland colony of cormorants in Wales, before spilling into the floodplain. In the years before drainage, it was covered by sea- the cormorants have long memories.
This walk explores the western, less-visited part of the valley. This landscape was scraped wide and flat by retreating glaciers, leaving the sky open and huge above, but is still defined by the mountains rolled across the valley-head like a cardboard stage-set.
Always in the foreground, the craggy volcanic intrusion of Craig-yr-Aderyn is clearly defined in bold inky lines when the peaks behind are blue.
1. Dykes and Ditches
Beginning in Tywyn, the path passes the WWII RAF camp to reach the salt-marsh where feathers and crispy bladderwrack strew the hummocky turf, while the gorse, reed-beds, bogs, dykes and ditches throng with wheatears, skylarks and meadow pipits.
2. Millennial Moss
Ragged robin and cottongrass grow in the bog. During the Second World War, children gathered sphagnum moss from here, which was sent to the frontline for use as a wound dressing. Starry-patterned sphagnum grows on the bog's surface. The older part of the plant floats underwater where the lack of oxygen means it decays very slowly. Over time, the moss becomes peat-moss, and over millennia, it becomes peat.
3. Broad Birdlife
The River Dysynni was used by peat-carrying boats until the river silted up in the late 19th century and ballooned into Broad Water, on which water birds squabble and swim. Cormorants breed here, too. They line up on the spit like charred black driftwood among the swans and geese.
4. Warbling Song
Leaving the lagoon, the river wends through whispering reed-beds whose rushes are explosive with songs of sedge warblers. Reed warblers, too, sing and swing on the stems.
5. Stop for a Break
The hawthorn banks of a sandy stream, where Welsh Black Cattle graze the water-meadows, bring you to Bryncrug where The Peniarth Arms is a good place for lunch.
6. Wild Quarry
Your return to Tywyn, after crossing the Dysynni via A493, is a quiet farm road. Blowsy with insects and honeysuckle hedges, Tonfanau Quarry frowns overhead while sheepdogs run in the stone-walled fields.
7. Water Meet
The lane rises and rolls, and brings you to the seafront, where the outflow from Broad Water is borne under the railway bridge to the beach. Meanwhile the floodplain delivers the valley, ever so gently, to the sea.
Julie Brominicks is a landscape and travel writer who lives off-grid in a caravan in a mossy Welsh valley.