Ninette Dreyfus, a young girl from grand Parisian stock, the Louis-Dreyfus family, did not know she was Jewish until the war broke out. When the Germans approached the capital, she and her family left for Marseille in a chauffer-driven Chrysler. They, like many others, were eventually forced to leave France in a perilous journey across the Pyrenees, a passage made in the rain to avoid sniffer dogs.

Her hands were so ragged that when the family reunited in Spain and her parents treated Ninette to a manicure, "the manicurist wept at the sight of her hands".

Former Today programme presenter Edward Stourton has walked in the footsteps of St Paul, Mohammed, Jesus and Moses. His latest journey is that of the Chemin de la Liberté, a commemorative four-day, 40-mile trek over the Pyrenees, in the footsteps of those, like Dreyfus, who escaped the Nazi collaborationist Vichy regime.

He tells the story of the many "parcels", smuggled over the mountains, from Allied airmen, whose planes were shot down over enemy territory, to Jewish families who had escaped the savage round-ups. And he tells of those who helped them, the pockets of resisters like the fearless Dédée de Jongh and her father, and of their betrayers.

Among stark descriptions of internment camp Le Vernet, of failed crossings, and of rogue guides holding their charges at gunpoint, there is fun. Clayton Hutton, escape expert at MI9 who created silk maps for vulnerable airmen comes across as a nutty professor, for whom "a fountain pen became a weapon for firing darts at German soldiers", and flexible saws somehow found homes in shoelaces.

The Earl of Cardigan makes a thrilling escape from a German patrol by pretending not to understand their thick accents, and British soldier Stan Hope almost reveals himself by shouting "corner!" at a football match.

However, too often Stourton's evident fascination strays into sheer delight at how exciting it must have all been. Calling Cardigan dragging a bicycle through bushes over the French border "pure Boy's Own derring do" seems, in context, a little inappropriate.

Perhaps the real issue is the book's breadth. There are many charming, quirky and emotive tales told - rather too many to keep hold of, something Stourton excuses himself for by arguing that "there is no neat way of telling this piece of history, it is a jumble of fragmented lives".

His exploration of the context of the Spanish civil war and Vichy regime is nuanced and informative but that, along with all the accounts of the escapees, their helpers and, lest we forget, Stourton's walk (or rather, how much he does not like camping) makes for rather a busy book. The tales of those fleeing are evocative, even gripping, and worth telling on their own merit. There was really no need also to hear quite how scary it was for Stourton to get back to bed from the loo using only the light of his Kindle.