I have never been a particularly gifted navigator, which is why my decision to drive a hire car from Alicante Airport to Cartagena was, in hindsight, a triumph of optimism over experience. Three hours of motorway, two wrong exits, and one spectacular argument with a satnav that insisted on pronouncing "La Manga" as if it were a Yorkshire village later, I finally spotted the sea glinting in the distance and felt something close to relief. Then I missed the turning for the apartment complex entirely, performed an illegal U-turn outside a petrol station, and watched in my rear-view mirror as my suitcase, which I had rather foolishly placed on the back seat without fastening, launched itself into the footwell like a dog eager for walkies.

The apartment itself, when I eventually found it, was one of those white-washed holiday lets that cling to the hills above Cartagena's port. I dumped my belongings, changed into walking shoes with the frantic energy of someone who has been sitting down for far too long, and set off towards the coast path before the sun could dip too low. This was October, after all. How hot could it possibly be?

Famous last words, as my grandmother would say. Within twenty minutes of descending towards Cala Cortina, the small beach tucked beneath the headland, I had shed my jumper, rolled up my trousers, and was seriously considering whether it would be socially acceptable to remove my shirt in a country where I barely spoke the language. The thermometer on my phone read twenty-six degrees. Back home in Manchester, people would be calling this a heatwave and stripping off in parks. Here, the locals were wearing light jackets and looking at me with the mild concern usually reserved for confused livestock.

I had planned, in that vague way one plans on holiday, to attempt a proper coastal hike the following morning. The trail east towards Portman, threading through the old mining country, was supposed to be spectacular. Rugged cliffs, abandoned workings, that sort of thing. I set my alarm for six, packed water and oranges from the mercado near the port, and fell asleep with the balcony door open to the sound of distant shipping.

What woke me was not the alarm but the rain. Not English drizzle, that polite persistent wetness one can walk through with sufficient stoicism, but proper Mediterranean downpour, the kind that bounces off terracotta tiles and turns streets into rivers. I stood on my balcony in my pants, watching palm trees bend like embarrassed party guests, and understood that my hiking plans were being rewritten by forces beyond my control.

By midday the rain had stopped, the sun had returned with what felt like personal vengeance, and the humidity had climbed to something approaching tropical. I walked anyway, because I am stubborn and had already eaten one of the oranges in a fit of breakfast disappointment. The path was steamy, the limestone slippery, and within half an hour I looked less like a serious walker and more like someone who had fallen into the sea fully clothed. I turned back at a viewpoint overlooking the bay, sat on a rock that was still warm from the morning's sun, and laughed at myself. There is something humbling about being defeated by weather you did not pack for, in a country whose climate you thought you understood.

The rest of the week settled into a rhythm dictated by the sky. Early walks before the heat built, afternoon retreats to the apartment's small pool, evening strolls through Cartagena's old town when the port lights came on and the temperature dropped to something civilised. I never did reach Portman. Instead I explored the headlands closer to home, found coves where the water was clear enough to count pebbles, and learned to read the morning clouds with the anxious attention of a farmer.

On my final day, I woke to perfect walking weather, that golden hour coolness that makes the hills feel possible again. I walked further than I had managed all week, following the coast path as it curved around the bay, and found myself on a ridge I did not recognise, looking down at the apartment complex where my suitcase still sat half-unpacked. I had spent a week chasing the right conditions, adjusting my ambitions to the mood of the sky, and had ended up somewhere unexpected. It struck me then that this was perhaps the point. Not the destination, not the planned route, but the adaptation, the willingness to walk when the walking was good and retreat when it was not. I sat on that ridge until the sun grew insistent, then turned back, already sweating, already smiling.