Dooey Peninsula, Co. Donegal

I nearly missed it. I'd been working my way along the coast near Meenlaragh, ready to turn back, when the sand patterns beneath the shallows stopped me dead. Pale gold bleeding into deep turquoise, these long curved ridges shaped by tidal flow, shifting every few hours into something entirely different. I held position and just watched.

From altitude, the whole structure of this coastline reveals itself. That long sandy spit holding the Atlantic back from the calm lagoon behind it. Rocky islands trailing northwest towards Tory, which sat on the horizon about twelve kilometres out, just a dark shape in the haze. Green fields running right to the cliff edge, as they do along so much of Donegal. It's a place that hides its real character at ground level.

The sky was overcast with a faint warmth creeping in from the right, probably the last trace of a sunset that never quite committed. Perfect conditions, actually. No harsh shadows, and that flat diffused light let the colour in the shallows come through cleanly. Direct sunlight would have scattered off the surface and hidden everything underneath. The lagoon was dead calm too, which helped enormously. Even a light chop and those sand patterns vanish.

Tory Island in the distance gives the whole image its sense of scale and exposure. Without it, you're looking at a beautiful beach. With it, you understand how far out into the Atlantic this corner of Ireland really reaches!