The concept was a simple one - to re-trace four of the greatest World War Two escape routes through Europe. Although there were obviously huge numbers of ways to leave occupied Europe during this period by finding a border into a neutral country, of course it wasn’t quite as simple as that.

Borders were invariably heavily patrolled, dividing lines between liberty and incarceration, between hope and despair. The Nazi’s and their Facist sympathisers were quick to spot this, and put in place measures to make sure that escape via normal border crossing points - roads, railways, ports - became almost impossible as the war progressed. And so the mountains became the preferred option - serried ridges, glowering peaks, vast ranges, and snow covered cols were not places where patrolling was easy after all.

Many classic routes sprung up during these latter stages of the war, as the full horrors of the Nazi regime became apparent, and as air raids led to more and more airmen being shot down over occupied territory. These routes became known as “The Freedom Trails” and I decided to follow them, all the while being filmed for a new Channel Four tv series.

But this was no casual undertaking. These treks would take me through genuine wilderness, and if not involving actual climbing, could certainly be classified as mountaineering. Such environments cruelly expose inadequate kit (I was to discover during my research some remarkable tales of survival and endurance occurred on these trails, as most who did them were pitifully ill-equipped). I knew I was going to need some decent gear, and invariably the best place to look in such situations is to turn your gaze to the north.

 Nordic Outdoor draw their equipment and clothing from Scandinavia, where it has been tested in an environment where the latitudes are high and the temperatures are low. Very low. I contacted the company and told them what I was attempting to do. They wholeheartedly supported the project - after all Scandanavia saw some of the most remarkable and heroic stories of resistance during the war - and immediately drew up a list of kit that would be required. When it arrived, my first impression was that you could feel the miles in it, the treks, the climbs, the descents, the long winter nights where your clothing was the only thing that is keeping you alive. In short there is real heritage in this gear. I tried it out on the few treks where I live in Devon and then, before I knew it, the date of the first trail was upon me.

This was - appropriately - through the second most forested European nation outside Sweden. Slovenia was the site of one of the truly great unknown stories of the war, where a bullish Australian called Ralph Churches and a young Englishman called Les Laws led over 100 POW’s for 150 miles through enemy held terrain to eventual liberation. The escape became known as the Crows Flight, and involved thirty more POW’s than the much heralded Great Escape beloved of book and screen. It was hushed up after the war as the escapees had been helped throughout by local partisans, considered at the time by the British Government to be communists. It is only latterly that this remarkable story has come to light.

Slovenia - as well as being heavily forested - is also one of the loftiest nations in Europe, with an average altitude of 400 metres. It’s important to note that given the constraints of time to film the programmes, I could only trek sections of the entire route, but the ones I picked were certainly the most dramatic. It is wonderful country, and the story of the Crows Flight is revered there. As such much of the route is well marked. I walked with a wonderful guide called Herman (who’s uncle had been a partisan), and together we trekked, talked, drank, and laughed our way through a nation that - until now - I had known almost nothing about. The forests are deep, dark, ancient and populated by lynx, wolves and bears - a fitting setting for one of the most dramatic escape stories of the entire second world war.

Both of the next routes took place in Italy. The first involved a feat of mental as much as physical endurance, with a Hackney boy called Len Harley who went on the run from a POW camp in late 1943 in a beautiful valley called Sulmona. For all of their appeal aesthetically, valleys - by their very nature - have the distinct disadvantage of being surrounded on all sides by hills. Len evaded capture within the valley for a staggering seven months, being sheltered for the majority of that time by a local lady called Rosina Spinosa. Eventually he made a run for it over the 2,900 metre summit of the nearby Monte Amaro, finally making his way to Allied lines after a monumental feat of endurance and fortitude. Even wearing the best gear, and fully rested and fed, Monte Amaro was a tough ascent for me - myself and local guides hit the summit just as evening was falling, and the drop in temperature that accompanied the falling of the sun was utterly pitiless. Fortunately there was a refugio nearby where we sheltered for the night before continuing our journey to the village of Fara San Martino the next day. Len and his fellow escapees did this entire journey in one go - a tribute to both him as a person, and to the power of pushing towards liberation, home and family.

There was to be a truly joyous conclusion to this trek. Through the research conducted in the course of making the programme, we had discovered the whereabouts of Rosina. Len had not seen her for 75 years, but had never forgotten her bravery and kindness. We had the great privilege of bringing them together after all those years - the clip on You Tube now has 2 million hits and continues to rise. A magical end to a wonderful trek.

Monty Hall Overlooking Pacentro - Sea Dog TV and Film Productions

The other Italian route covered the exploits, and subsequent escape, of one of the most famous SAS operations of the war. Operation Galia saw 33 men parachuted into occupied territory to create chaos and bedlam behind the Gothic Line, the German forces final defensive barrier in Italy. After over forty days in theatre, they finally made their way home over the Appenine Mountains, pursued throughout by thousands of German troops. My route took me over the Marble Mountains and down towards the Mediterranean coast. The view from the knife like ridges at the summit of Monte Altissimo, as the meandering sapphire ribbon of the coastline stretches away beneath you, is one that will stay with me forever.

The final route was the daddy of them all - the Path O’Leary Line over the Pyrenees. It is estimated that 33,000 civilian refugees, and at least 3,400 Servicemen, made it over the Pyrenees into neutral Spain during the course of the war. As I found out on my own trek, this was no small feat. As various lower routes were betrayed and compromised, the trails were forced higher and higher into the mountains, until in the end traversing the border required a route that took in three high ridges that - in total - were half the height of Everest. This was perhaps the trail where the feats of those who made it struck home hardest. It was breathtaking in every sense of the word, but for the escapees such treks generally took place in the depths of Winter. Many did it with small children, or carrying suitcases, or desperately weakened by lack of food. Virtually all did it with inadequate clothing.

But the moment in my own trek when I realised what spurred them on came when we crested the final ridge leaving France, and looked down into Spain for the first time. For thousands of people in the war, those last faltering up the steep slope were taken as fugitives, and then - in the space of a few metres of travel - they descended the other side as free citizens of the world. It must have been a moment that made every minute of suffering entirely worthwhile.

And the kit? Tougher than me, that's for sure. I found the Merino wool tops particularly useful - cool in the sun, but a brilliant underlayer when it got chilly. I know it’s been well recorded with Merino, but it’s a truly miraculous natural fibre, and how it doesn’t smell to high heaven after a week of trekking I’ll never know. I actually descended into Spain moderately fragrant - at least in my own mind anyway. My favourite bit of kit though was the Fjällräven trousers with the G-1000 material. I’m not quite sure what this material is, but can only assume it is made by Vikings using the spun hair of rams that live on glaciers, perhaps mixed with a few feathers of snowy owls and the innards of an Arctic fox.

It’s great stuff. I’d urge you to try these routes - they're well recorded and marked in the relevant countries, and a little research reveals them in all their glory. We all want to walk trails that have meaning, and with these you truly follow the footsteps of giants.

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