Country diary: the Afon Leri reflects the reeds on a clear winter's day

Borth, Ceredigion: Arrow-straight as a result of canalisation in the early 19th century, the river once had a meandering path into the open sea

As soon as I reached the top of the sea wall, I realised that I had badly misjudged the state of the tide. Instead of miles of firm sand, recently exposed by the retreating sea, I was faced with a jumble of storm waves breaking against the bank of stone cobbles at the back of the beach. My objective, the dunes of Ynyslas a couple of miles to the north, was temptingly visible through a shroud of misty salt spray - but, stumbling across the shifting, irregular stones, I made only slow progress. Cursing my cursory examination of the tide tables, I realised I had read the time for high water, rather than low.

After I had walked for half an hour, the dunes looked as far away as ever and I began to consider alternatives. Looking east, beyond the ridge of stones and the Afon Leri, I could see the great flat expanse of Cors Fochno - a rare survival of raised peat bog, which forms a key part of the Unesco-recognised Dyfi biosphere. With a backdrop of steep, open hills, this diverse wild landscape is an important ecological resource, protected both by statute and its sheer inaccessibility.