The omens are equivocal. It is not actually raining, but as I choose my clothes at 7 a.m., Kirsty, still in her nightdress, comes into my room. "Margot," she says, "why aren't you married?" Why indeed, I think, skidding wildly down some long, dark alleyway into the past. "I forgot," I say. "Should I wear my black jeans?" But Kirsty, a diligent questioner, is not so easily put aside. "Why did you forget?" she asks.

I am in Edinburgh, visiting Kirsty and her parents, and today is set aside to go to Glenalmond, the valley where I grew up. As I drive out of the city, I do my best to put aside Kirsty's questions. Instead I ponder this mysterious business of a journey with its implied beginning and ending. But Glenalmond was not a place I ever journeyed to -- it was the place I was, most fully and completely -- and if I am to journey there now, I need a place to start. Where should I begin?: America, where nowadays I mostly earn my living? London, where I spend summers? Kirsty's house? I round a bend and suddenly the road unwinds before me in total familiarity. I am in Blackhall, an Edinburgh suburb, and the answer is obvious.

Just a few yards from the main road is 4 Craigcrook Place, the home of my redoubtable great aunts. The old heavy door has been replaced, but there is nothing newfangled, like a lock or an intercom, to bar my progress. Inside even the dustbins seem unchanged.The aunts' flat was the outermost star in my childhood cosmography. We visited them twice a year, an immense journey for which my stepmother packed sandwiches and a thermos of tea. Now I whiz there along modern roads. An hour later I am entering Methven, the drab village where we came to catch the bus, post letters, buy treats. I stop at Lawson's garage, where my father brought his cars, each more decrepit than the last, all called Henry. The man who sells me gas tells me that Mr. Lawson died shortly before Christmas. I tell him I am going to Glenalmond. "Oh, you'll notice lots of changes," he says. "All the big houses." I imagine the valley filed with skyscrapers: Manhattan in Arcadia.

Opposite the post office I turn off for Glenalmond. The narrow road climbs steadily for four miles, and every bend and hummock is familiar. When I broach the final rise into the valley, my heart is racing, and I pull over. Gradually the tink-tink of the motor fades until I can distinguish the sounds we casually call silence: the wind in the fields, the hum of insects, the bird song. On the far side of the river a long line of hills fills the horizon. Looking from east to west, I see the slate quarries, the circular wood, and the dark, scree-covered slopes of Sma'Glen.