When Harri was about 18 he bought a copy of Tony Drake's book, The Cambrian Way, in an outdoor shop opposite Cardiff Castle.
From that day on, he always hoped he would one day complete the high level walk described on the official website as 'traversing the highest and wildest parts of Wales'.
At 275 miles, the Cambrian Way is nearly 100 miles longer than the popular Offa's Dyke Path; it is also far more physically demanding with an overall estimated ascent of 61,540 feet (18,742 metres).
The route is not waymarked and so requires good navigational skills (map-reading and compass).
When Harri and I met back in 2006, he was still enthusiastic about walking the Cambrian Way, though realistic about the difficulties of completing it in one go. A year or two later, as he began to establish his outdoor writing career, he managed to get a publisher interested in the project. Unlike Tony Drake's book, Harri proposed to provide clear directional advice so that hikers would be less likely to lose their way.
Sadly, despite walking most of the Cambrian Way over a series of holidays and long weekends, we never quite completed the project. The publisher lost interest and it soon became apparent to Harri that certain sections of the route, e.g. the Rhinogs and some of the Snowdonia peaks, can be extremely dangerous in bad weather conditions, even in summer. Harri himself was caught in a white out in Snowdonia (at the end of April) and forced to clamber over treacherous and very slippery rock faces in the water-logged Rhinogs (in August).
Yet the idea of walking from one end of his country to the other had taken root and, as anyone with a heartfelt ambition knows, sometimes you just have no choice but to go back to the drawing board.
After a lot of time poring over the numerous OS maps covering Wales, Harri came up with an idea. The Welsh phrase O Fôn i Fynwy literally means from Anglesey to Monmouthshire but is also used figuratively to mean the whole of Wales. Why not devise a long-distance walk from west to east, starting in the north-west town of Holyhead and meandering south through Wales to Chepstow?
Harri's route would be undulating and demanding (this is Wales after all) but, unlike the high-level Cambrian Way, still well within the capabilities of anyone with a reasonable level of fitness. Moreover, it wouldn't present hikers with the ultimatum of continuing across high mountains in extreme weather or pulling out, because the highest peaks would be outlined as optional detours.
At around 400 miles (the exact distance is yet to be calculated), it would also be a much greater challenge than Wales's existing National Trails, the Pembrokeshire Coast Path (186 miles/299 km), Glyndŵr's Way (135 miles/217 km) and Offa's Dyke Path (176 miles/283 km).
We walked O Fôn i Fynwy in June, leaving Holyhead on June 2 and arriving in Chepstow on June 24. It was tough going at times and we faced some steep climbs, e.g. the Cadair Idris pass, Carmarthen Fans, Pen y Fan. Harri's route takes in some of Wales' most breathtaking mountain scenery, including waterfalls, rivers and lakes, follows miles of the Wales Coast Path and visits some of the prettiest places our small country has to offer.
Like the late Tony Drake, we've stuck to public rights of way, but wherever possible, we've used existing waymarked trails like the North Wales Path, the Ardudwy Way, the Beacons Way and the Wye Valley Walk as they are usually better maintained and signposted than other footpaths.
We're still refining the route - we'll be returning to mid Wales in July to check out some alternatives to the route. If all goes as planned, we aim to publish the guidebook by early autumn. In the mean time, I'll be sharing some of our experiences with readers of The Walker's Wife across the world.
Our hope is that one day O Fôn i Fynwy will be recognised as Wales' fourth National Trail. In the meantime, we just want to introduce outdoor lovers from across the world to this beautiful country we live in.
O Fon i Fynwy - walking Wales from end to end by Harri Roberts and Tracy Burton will be published by camau later this year (2014).
A more detailed version of this blog will be published in an accompanying ebook later this year.