To walk all the way home, that was the plan. Once the idea had taken hold, for a soft city-dweller it gathered an irresistible green logic.

It would involve a bit more than just getting off the bus a couple of stops early, however. Doing it properly would mean taking Offa’s Dyke Path, one of the splendid National Trails, which hugs the England-Wales border from the Severn Estuary to the Irish Sea and which passes close to the village where I grew up, a few miles from the North Wales coast. I haven’t lived up there for more than 40 years, but in the recesses of my mind, cached along with memories of hopscotch and chilblains and church twice on Sundays, I still think of Caerwys, Flintshire, as home.

The path extends 177 miles (280km) from Chepstow to Prestatyn, large chunks of it alongside, crisscrossing, or even proudly surmounting the enigmatic ridge of ancient earthwork that is the dyke itself. Archaeologists believe that it was built some time in the late 8th century either to mark the border (and so the term March, or Marches) or as a defensible barrier between Wales and the kingdoms of Mercia to the east. I wouldn’t have time to tackle the whole distance, so the northern section upwards from Knighton in Powys would have to do. About a hundred miles in all, a knapsack on my back, and six free days in which to do it.

The hotel in Knighton I had chosen from the Offa’s Dyke Association website turned out to have been the boyhood home of that indefatigable explorer Wilfred Thesiger. A good omen, I reckoned. I even had the bedroom that had once been his and I lay on my back thoughtfully examining the plain ceiling, just as he must have done on similar summer nights.

From the steep height of Panpunton Hill immediately outside Knighton, the view the next morning was of silver loops of the Teme in the valley below, and the Path winding ahead. The “switchback” on the way to Montgomery has the reputation of being the toughest of the route. Certainly there was a series of sharp ascents and descents, but none was long, the conversation was interesting and there were views of turfy hills and dreamy, hidden valleys. It was only at the end of the day, tired, that I felt pleased not to be camping on this expedition. The landlady of our B&B was waiting, having driven out of town, and she walked up the path to meet us. I caught sight of her, standing like Ruth in an empty cornfield, with her skirt fluttering around her calves.

The next day I followed a mile of the Montgomery Canal, then crossed a broad, flat stretch of the Severn Valley with the dark Breidden Hills marching alongside. At Four Crosses there was a bleak pub. There were two other walkers at breakfast. One of them zipped up his Gore-texes, strung his transparent plastic map case across his chest and strode out into the downpour. The other confided that he’d had enough of the vile weather and was packing it in this very day.

I ventured out, deciding to take the main road into Llanymynech rather than go the longer way on the Path. Big mistake. The road was covered by floodwater. I had walked no more than 200 yards before a lorry accelerated through a medium-sized lake. I caught the resulting cataract full in the face, and was soaked. I called a taxi, and booked into a spa hotel in Oswestry for a massage. Go with the flow. Thesiger wouldn’t have had to deal with rain like this, out there in the Empty Quarter.

The next day was a reward in itself, as I surged onwards from Oswestry, past Chirk, over Telford’s glorious aqueduct at Pontcysyllte and across a high scree section above the dainty valley of Llangollen, with Dinas Bran Castle etched against the sodden sky.

The fifth day was spent exultantly swooping down the saddles and over the exposed tops of a chain of hills that would lead to home. In the afternoon I finally came round the shoulder of Moel Arthur, crowned with another in a series of fine Iron Age hill forts, and away to the right lay Caerwys in its cup of fields.

It looked the same as it always did, with only a rash of new building at the grey stone edges to indicate that this was not 1957. Here was the sky-line that I could see from my bed. That night, I stayed with family.

Nothing much has changed, except that now there is one empty chair.

At last, the sun came out. The last 12 miles, over the uplands from Bodfari down to Prestatyn, were scented with gorse and honeysuckle, and the swooning waft of white clover. Sunlight sparkled on the sea, stretching ahead of us from Llandudno to Liverpool. We marched down the high street, past the cafés and the station, over the beach wall and down the dun-coloured sand right to the point where small grey wavelets broke over our boots. Ahead, new to me, the huge arms of offshore wind turbines lazily rotated. There are new oil rigs too, farther out, blowing plumes of flame into the sky.

The hills and the valleys and the plains I’d walked over, bone and sinew of the landscape, those have been there and always will be there, for ever. I had walked home.

Need to know
The Offa’s Dyke Association website (www.offasdyke.demon.co.uk) has information on accommodation, transport, maps and guides.

Reading:
Offa’s Dyke South, Chepstow to Knighton and Offa’s Dyke North, Knighton to Prestatyn, Aurum Press (£12.99 each).
Useful condensed maps of the North and South Offa’s Dyke Path from Harvey Maps (01786 841202, www.harveymaps.co.uk) are £9.95 each.

Where to stay:
Milebrook House Hotel (01547 528632, www.mile brookhouse.co.uk) in Knighton offers B&B from £49.75pp.
The Old Stores House (01686 668617, www.montybandb.co.uk) in Montgomery has B&B from £22.50pp.
Tyddyn Llan Hotel (01490 440264, www.tyddynllan.co.uk) in Llandrillo charges from £95pp for dinner, bed and breakfast.

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