I’ve always loved the sea. The metronomic crash of Pacific breakers lulled me to sleep and washed through the waking hours of my childhood. Ceaseless, powerful, hypnotic, the sea is oblivious to human need; a restless creature, always stirring.

This summer, I visited lakes. Some I merely looked across: Upper Klamath Lake, Mono Lake, Topaz Lake, Eagle Lake: tiny blue blotches on the road map that, beneath high, cloud-dotted blue skies, resolved themselves into shimmering pools between the flanks of golden-grassed hills. They reflected the slanting light of later-afternoon sun, flashing into my eyes like a signal from a giant’s pocket-mirror. I felt a little sorry for them, so still and self-contained.

In Yosemite, my friend and I drove forty miles out of our way to Tanaya Lake, set high in the Sierra Nevada mountains. We almost turned back – what could possibly be so interesting about a lake? It came into view suddenly, like a character in a film stepping through a door. The air was 8000-feet-high cool but the morning sun had already warmed the slabs of limestone that hemmed the lake. It was deep blue shading to green. Streaks of snow highlighted the mountaintops to the east. The southern end of the lake melted into an evergreen forest. I sat on the sun-warm rock and realised that I was holding my breath, as if it might disturb Tanaya’s pristine surface, or imperceptibly affect the tenacious, inches-tall pine tree ardently creating itself in a crevice at my feet.

The perfect lake, it seems, embodies stasis. Crater Lake – a flawless liquid sapphire set in the collapsed heart of a volcano. Nearly two thousand feet deep, and almost eight thousand years old, its Siren blue absorbs everything and nothing. No tributaries run to it; it supplies no stream or river; it flourishes on the icy nourishment of snowmelt and moonlight. It is infinity in the palm of Vulcan’s hand, terrible, beautiful and untouchable as myth.

Lake Tahoe is different, lighter. Wavelets run eager tongues across its white sand beaches, waggling in the wake of speedboats and wheeling jet skis. Crystalline shallows shade into turquoise and azure, a sparkling mimic of the firmament. Of all the lakes, it comes nearest the hue of my beloved Mediterranean. Only instead of a horizon running to the sky it is snugged in the rocky embrace of the Sierra Nevadas. It didn’t make me sad, like some of the others, but it didn’t stir me, either. It borrows its vitality, moves only at the behest of urgent outboard motors, or the thin breath of alpine winds. No restless grandeur shivers its depths and makes it leap and grasp, time and again, for something it will never reach.

I will always love the sea.