The ferry from the mainland to Arkoesund was meant to take twelve minutes, which I only know because I spent the first eight of them frantically patting down every pocket I owned. My hire car keys. Gone. Not in the jacket, not in the trousers, not in that ridiculous zip compartment I always forget exists. The ferry ploughed on through water the colour of weak tea, and there I was, performing what can only be described as a panicked self-frisk in front of a Swedish family who were definitely trying not to laugh. Found them eventually, of course. In the ignition, engine running. I'd left the car running the entire time. The father gave me a sympathetic nod that said "we've all been there," though I suspect his version of "there" involved slightly less public humiliation.

September in Ostergotland has a particular temperament, and that temperament is "make up your mind." The morning had started grey and spitty in Norrkoeping, the kind of drizzle that doesn't bother falling properly, just hangs about making everything faintly damp. By the time I'd navigated the winding roads through pine forests and past fields of stubble where something golden had recently been harvested, the sky had performed one of those theatrical Swedish clearances. Blue appeared in ragged patches, like someone tearing open a parcel they weren't sure about.

The cottage sat where the property description promised, perched on the archipelago's edge with a deck that jutted toward the water like an optimistic diving board. First impression: smaller than the photos suggested, but somehow more solid for it. Red wooden walls, white trim, the whole thing looking like it had grown from the granite rather than been built upon it. The surrounding birches had begun their autumn turn, leaves fluttering down in that tentative way they do when they're not quite committed to falling yet. A few brave ones landed on the deck and stayed there, too polite to blow away.

What struck me immediately was the light. Not the quantity of it - September days are already shortening - but the quality. Low, angled, somehow personal. It picked out the texture of the wooden cladding, the rust on a small anchor someone had left as decoration, the way the water beyond the deck shifted from steel-grey to sudden green where shallows met rock. I stood there with my ridiculous wheelie case and felt that particular autumn melancholy that isn't quite sadness, more a recognition that something is ending and you're present for it.

The temperature had that Nordic specificity: cold enough to need a jumper, warm enough in direct sun to regret it. I kept putting mine on and taking it off, a ridiculous dance performed on the deck while a couple of ducks watched from the water with what I interpreted as avian judgment. The air smelled of pine and something else, something I eventually identified as woodsmoke from a distant chimney. Someone, somewhere, had already surrendered to the season and lit a fire.

I unpacked badly, too distracted by the view through the kitchen window. The property's location meant the sea - or the Baltic, or whatever we're meant to call this particular stretch - dominated every room. Even the bedroom, tucked at the back, had a sliver of water visible if you stood at precisely the right angle and accepted "view" as a generous term. I found myself inventing reasons to pass through the living room, to catch another glimpse of how the changing light altered the water's mood.

By late afternoon, the temperature had dropped properly. The kind of drop that announces itself through your ankles first, then works upward. I retreated inside and discovered the cottage's heating system with the enthusiasm of someone who has just remembered what "cold" actually means. The radiators clanked and hissed in that reassuring way old systems do, and I sat on the sofa with a cup of tea that steamed dramatically in the fading light, watching the first stars appear where the sky had cleared completely.

That evening, I walked the short path down to the water's edge, the granite rough under thin-soled shoes I'd foolishly packed. The tide was doing something complicated, or perhaps the Baltic doesn't really do tides properly and I was imagining things. Either way, the water moved with a restlessness that felt seasonal, anticipatory. Summer's calm had departed; something more interesting was arriving. I stood there until the cold became actual discomfort rather than atmospheric charm, then retreated to the cottage's warmth, leaving the darkness to settle over the archipelago without me.

The mishap with the keys feels appropriate now, a small absurdity that matched the month's own indecision. Summer refusing to leave, autumn pressing to enter, me caught between jumper on and jumper off, the cottage holding its ground against the gathering dark with the quiet confidence of somewhere that has seen many such transitions and knows how to outlast them.