In The Mercian Challenge you take on 100 miles of the Offa’s Dyke footpath from Chepstow to Montgomery, tackling the 703m Black Mountain, and a total of 5180m of elevation along the way; This is no ordinary 100 mile event. It is a immense challenge in its own right, hence the 42 hour cut off time.

You can download the map and GPS pack hereUPDATED 22:00 9th September 2019] It includes

  • GPX file for upload to a GPS device
  • A Google Earth KML file

Mercian Challenge Elevation

Offa’s Dyke footpath starts on the shore of the Severn Estuary in Sedbury on the outskirts of Chepstow.  The path then heads into Chepstow itself, passing on the opposite side of the river from Chepstow Castle.

Chepstow castle

Chepstow castle

The path then follows the River Wye for 18 miles to reach Monmouth and indoor checkpoint 1. You then strike West then North West for 17 miles, passing Whitecastle to the village of Pandy and indoor checkpoint 2.



You must now steel yourself  for the mountain section ahead.  Climb rapidly to Hatterrall Hill (531m) and then along the spectacular 8 mile ridge to Black Mountain, reaching 703m before following the path off the ridge shortly before Hay Bluff, descending all the way to reach major indoor checkpoint 3 at Hay-on-Wye (51.3 miles).

Hay Bluff

Hay Bluff

An undulating section now follows as far as Gladestry before a sharp climb up and along Hergest Ridge before a long enjoyable descent to indoor checkpoint 4 at Kington.

Hergest Ridge

It’s a immediate climb out of Kington to Rushock Hill, following the dyke earthworks to contour then descend Herrock Hill, before contouring around Burfa Camp towards Evenjobb (Einsiob) and they Dolley Green and then on to Knighton (Tref-Y-Clawdd) to the indoor checkpoint 5 at the National Offa’s Dyke Visitors Centre.

Offas DykeVisitorsCentre

Offa’s Dyke Visitors Centre

You then cross the River Teme and climb to pick up the Dyke and traverse the Clun Hills, skirting Newcastle, and Church Stoke before finally diverting off the path to reach the finish line of The Mercian Challenge  in Montgomery.

Offas Dyke

Photo by 2007