The rain is falling like fairy dust. It's drifting down from the smudged, white sky. The sparrows are chattering, clinging onto brickwork and rattling off calls. One swoops up into the nest right outside my open balcony door. I hear a burst of cheeping, hungry mouths that never seem to be sated. 

Pen y Fan is a popular mountain for a reason, it's not technical, you can do it in a few hours and it's easy to reach. And yet many people hike it ill-prepared. It's not a day for flip flops folks.