Walking: Crossing the dividing line: Tony Kelly spends a day visiting two countries, taking in the Wye Valley and Offa's Dyke

CHEPSTOW, where England meets Wales and the Wye flows into the Severn, is the starting point for two long-distance footpaths. The Wye Valley Walk follows the river for 75 miles through Monmouth, Ross and Hereford, before ending in Hay-on-Wye. The Offa's Dyke Path is longer, hugging the border for 168 miles all the way to the Irish Sea.

Keen to sample both of these walks, my wife Kate and I devised a day's walking, beginning and ending in Chepstow and taking in the scenery of the lower Wye Valley. The river Wye here is also the border - we would spend the morning in Wales, following the Wye Valley Walk to Tintern, then cross into England and return along Offa's Dyke on the river's east bank.

We parked outside Chepstow Castle, which sits on a massive limestone cliff overlooking the Wye. The Great Tower dates from Norman times but most of what you see is much later, an exhibition of changing architectural styles from the 11th to the 16th century.

The name Chepe Stove is old English for 'market town', although there are also signs for Cas Gwent ('Castle Gwent' in Welsh) and the Normans named the town Strigoil - 'bend in the river'. Most of Chepstow is in Wales, but the town suffers from something of an identity crisis. A recent council survey showed that many tourists did not know they had been in Wales.

Following waymarked signs, we left the town behind, skirting a school playground. Soon we were high above a deeply wooded valley, with occasional glimpses of the river through the gaps in the trees, our only companions the squirrels and a young man who jogged past us in hiking boots with a rucksack on his back.

At Wynd Cliff the path crosses a minor road before climbing circuitously to the 'Eagle's Nest' on top of the 700ft cliff. From here you can see into seven counties and also have a good view of the Severn Bridge. It was a favourite spot for 19th-century lovers and poets, and in 1828 the Duke of Beaufort built the 365 steps to the summit. These make a steep short cut, but we decided to stick to the longer footpath.

From here we walked along the Black Cliff with farmland to our left, stereotypically Welsh with its dry-stone walls and new-born lambs, even though England is only half a mile away. Eventually, six miles from Chepstow, the path dropped back down towards the river, and Tintern Abbey came into view.

Tintern Abbey inspired Wordsworth to verse and it is easy to see why when you first set eyes on the ruined shell. The windows and roof are gone, but enough remains of this 13th-century Cistercian monastery to get an idea of how it once looked; at the same time, it is ruined enough to be romantic.

The roof was stripped of its lead when the monasteries were dissolved and the building became a metalworks - the first place to make brass. Now it is a popular tourist site, and perhaps the finest remaining example of medieval monastic architecture in Britain.

'Could you take your boots off please?' the landlady at The Anchor called across the bar as I sat down with my pint. The food was overpriced and uninspired, the monastic-theme menu aimed at the coach parties who were there even in March, and two scruffy walkers clearly didn't fit the required image.

After lunch we crossed the iron bridge over the Wye and followed signs uphill through the woods towards Offa's Dyke, frequently turning to look back at the abbey, sadly partially obscured by scaffolding. Offa's Dyke is waymarked with the symbol of an acorn, so it was easy to walk without constant reference to the map.

After a mile we reached the Devil's Pulpit, a rocky outcrop overlooking the abbey and the river, from where Satan is said to have preached to the monks building the abbey, appealing in vain for them to stop the work.

The dyke was built by Offa, King of Mercia, in the 8th century, and parts of the original earthworks remain, but the footpath cannot follow the precise route, and eventually we were directed off the dyke, away from the river and on to a road. Perhaps my map reading was at fault, but there followed the most frustrating part of the day as we spent an hour and a half on the B4228 through Broadrock and Woodcroft, before finally rejoining the path for the descent into Chepstow.

Croeso i Cyaru said the sign as we walked back into Wales over the bridge we had crossed by car that morning. Walking from one country to another and back was certainly a new experience for me. And despite the disappointments of late afternoon it had been a good day's walking. 12 miles, hilly in places, not too easy but not too strenuous either, with beautiful scenery and an interesting stop half-way.

(Photograph omitted)