Road running is useful: you can cross the miles off without thinking too much about it, knowing your legs will take you where you need to go. No need for maps or fuel (mostly), and no need for much planning.
But if you’re suddenly faced with a bit of free time and a glorious day, why not seek out a route less travelled? Armed with little more than a sense of adventure and a slice of flapjack, you too can call yourself a trail runner. Going off -road needn’t be a full-on multi-stage ultra – although it can be if you want it to – it can be as simple as your local parkrun.