Offa's Dyke Path

The path starts on Sedbury Cliffs, above the Severn estuary, at a boulder with a plaque on it, and meets the dyke almost at once. For most of the first day it keeps to the English bank of the Wye, passing east of Chepstow and following the river high on its wooded escarpment, often beside the bank and ditch themselves: some of the dyke's best-surviving stretches are in the woods near Tintern.

Wintour's Leap is a line of limestone cliffs over the river, named for a Royalist said to have jumped from them in the Civil War and swum to Chepstow. He did escape his pursuers by the river, twice, but from lower places, at Lancaut and at Sedbury, where the walk began. Further on, the Devil's Pulpit, a limestone rock 198 metres up by our terrain, looks straight down on Tintern Abbey on the far bank; the story is that the Devil preached from it to the monks below.

The path comes down to the river at Brockweir and crosses into Wales at Redbrook, then climbs to the Kymin, 256 metres by our terrain, above Monmouth. On top are the Round House, built in the 1790s by a Monmouth dining club, and the Naval Temple of 1800 for the Battle of the Nile; Nelson visited in 1802. Both belong to the National Trust. Then down into Monmouth, where three rivers meet, past the Monnow Bridge, the only fortified river bridge left in Britain with its gate tower standing on the bridge.

It is 29.7 kilometres from Sedbury Cliffs to Monmouth on our line, with 830 metres of climb, much of it in the woods above the Wye.

The dyke is absent from this stretch. The path crosses the gently rolling farmland of Monmouthshire, among orchards that mostly grow apples for cider, by field paths and stiles from village to village: Llantilio Crossenny, then Llangattock Lingoed, whose churches the National Trail says are worth a stop.

In between is White Castle, one of the Three Castles, with Grosmont and Skenfrith, that guarded a lordship in the Welsh Marches from the twelfth century. What stands is mostly thirteenth-century stone, around an inner ward ringed by a deep moat cut from the rock; the name comes from the white render once on its walls. Cadw looks after it.

All day the view ahead fills with the hills to come: the Skirrid, and the long line of the Hatterrall ridge. The path ends the day at Pandy, at its foot.

It is 26.3 kilometres from Monmouth to Pandy on our line, with 451 metres of climb: one of the gentlest days of the walk, and the last before the mountains.

From Pandy the path climbs steadily onto the Hatterrall ridge, the eastern edge of the Black Mountains, inside the Brecon Beacons National Park, and stays on it for about eleven miles to Hay Bluff. To the west is the Vale of Ewyas, to the east the Olchon valley. The upland is a Site of Special Scientific Interest, and in mist it is a place to know where you are: the National Trail counts it among the hard-going upland stretches of the walk.

Below the ridge in the Vale of Ewyas are the ruins of Llanthony Priory, founded for Augustinian canons around 1100 and closed by Henry VIII in 1538; Cadw looks after them, entry is free, and a hotel stands within the grounds. It is a steep way down and back up for a bed.

The ridge reaches the highest ground of the whole walk near Twyn Llech, 703 metres by our terrain, then runs on to Hay Bluff and drops to Hay-on-Wye. Hay is the town of books: Richard Booth opened his first bookshop there in 1962, there are now more than twenty, and the Hay Festival has been held there since 1988.

It is 25.9 kilometres from Pandy to Hay-on-Wye on our line, with 633 metres of climb, most of it in the first hours out of Pandy.

Out of Hay the path follows the Wye for a while and then turns north into rolling country that the Victorian curate Francis Kilvert wrote about in his diaries. The church at Newchurch is left open for walkers. After Gladestry comes Hergest Ridge, a long hill across the border between England and Wales, 418 metres on the path by our terrain. On its top are a clump of monkey puzzle trees planted in 1988 and the line of a Victorian racecourse, and Mike Oldfield, who lived nearby, named an album after it.

Kington, below the ridge, was a livestock town on the drovers' roads. Beyond it the path crosses Bradnor Hill, whose golf course the National Trail calls the highest in England, and at Rushock Hill it meets the dyke again for the first time since Redbrook, more than fifty miles back. Powys, which it enters here, has more of the path than any other county.

The last miles cross the River Lugg at Dolley Green and come over the hills to Knighton, whose Welsh name, Tref-y-Clawdd, means the town on the dyke. The path was opened here on 10 July 1971, by Lord Hunt, leader of the 1953 Everest expedition, and the Offa's Dyke Centre is here. Knighton is almost halfway; its station, on the Heart of Wales line, stands just inside England.

It is 46 kilometres from Hay-on-Wye to Knighton on our line, with 1,299 metres of climb: two days at the planner's steady pace, with Kington between.

North of Knighton the path reaches the switchbacks: the hills of the Clun Forest in the Shropshire Hills, crossed not along but against the grain, down into each valley and up the other side. The National Trail calls this the toughest section of the walk. It is also where some of the best-surviving stretches of the dyke are, bank and ditch running over the hills, and at Llanfair Hill it reaches its own highest point, 430 metres.

Newcastle on Clun, in a valley between the climbs, is the true midpoint of the walk. After Hergan the Shropshire Way joins for a while, and then the path crosses the Kerry Ridgeway and the ground eases towards Brompton Crossroads, below Montgomery.

From there the going is gentler, on field paths along the dyke where it still marks the border itself. Montgomery is a short way off the path, with a ruined castle above the town. Then the path climbs over Long Mountain, past the earthworks of a hillfort, and comes down to the River Severn at Buttington, near Welshpool.

It is 43.5 kilometres from Knighton to Buttington on our line, with 1,249 metres of climb, most of it before Brompton Crossroads.

After the switchbacks comes the flattest part of the walk, along the Severn and the towpath of the Montgomery Canal, which once carried lime to improve the farmland. In very wet spells parts of it flood. The Breidden Hills rise to the east, with Rodney's Pillar on top. At Llanymynech the border runs along the main street, and the old limestone works include a Hoffmann kiln, which the National Trail calls the best kept of its kind.

Then the path climbs again, over Llanymynech Hill, whose disused quarry is now a nature reserve grazed by sheep, and on to Moelydd, 284 metres by our terrain, with a toposcope and views all round. It goes past Trefonen and across the old racecourse above Oswestry, over Selattyn Hill and down past Chirk Castle, and walks the last stretch of the dyke itself, which the path leaves for good near the Llangollen Canal.

Above the Dee at Froncysyllte the path turns back on itself and comes down to cross the river at Pontcysyllte. Just downstream is Thomas Telford and William Jessop's aqueduct, opened in 1805: 307 metres long and 39 metres above the river, the highest canal aqueduct in the world and part of a World Heritage Site since 2009. Our line crosses on the road bridge below it; the National Trail offers the aqueduct as a permissive way across.

It is 47.8 kilometres from Buttington to Pontcysyllte on our line, with 818 metres of climb: two days, one flat, one not.

North of the Dee the path enters the Clwydian Range and Dee Valley landscape it keeps almost to the end. It passes below Castell Dinas Brân, the castle the princes of northern Powys built in the 1260s on the site of an Iron Age hillfort above Llangollen, and runs along the foot of the Eglwyseg crags, the long limestone escarpment towards World's End.

Beyond, it crosses the moor and the forest at Llandegla, which the National Trail says holds the largest population of black grouse in Wales; in spring the males display on patches mown for them.

Then the Clwydian Range itself: a heather ridge over a string of Iron Age hillforts, Foel Fenlli, Moel Arthur and Penycloddiau, with Moel Famau, the highest of the range at 555 metres, between them. On its top is the Jubilee Tower, begun in 1810 for George III's golden jubilee and brought down unfinished by a storm in 1862. The views go west across the Vale of Clwyd to Snowdonia and east to England. The path comes off the ridge to Bodfari.

It is 46.4 kilometres from Pontcysyllte to Bodfari on our line, with 1,355 metres of climb: the most of any chapter, over two days.

The last day stays in the Clwydian hills, smaller now, on field paths through farmland with stone stiles north of Marian Cwm that the National Trail says are found nowhere else on the walk. The sea comes into sight in glimpses, then fills the view, with the wind farm off the coast.

From Prestatyn Hillside the path looks along the North Wales coast to Snowdonia, then drops through the town to the beach. The end is marked by a steel and limestone sculpture, Dechrau a Diwedd, the beginning and the end. Prestatyn is not on the dyke itself, but the custom is to finish in the sea.

It is 18.8 kilometres from Bodfari to Prestatyn on our line, with 482 metres of climb, and the station is 800 metres from the end of the path.