Of the many things we would tick off our list of cultural experiences in the US, I hadn’t really considered low-budget air travel as high on the list. We were flying Frontier from Des Moines to Denver, dumping our “executive SUV” (as the Budget salesman pimped it when selling in the upgrade; we were so over-tired and jetlagged we didn’t even notice we were being upsold, we were too busy nodding and signing anything he put in front of us) that had so comfortably conveyed us across the past 1300 miles.

It was in South Dakota and Grinnell when it sank in: Americans really are nice to each other practically all of the time. And they mostly seem to really mean it. This comes as complete culture shock to any Brit, I suspect, but particularly to Londoners. Our lives as social animals revolve around restraint, concealing or counterfeiting emotion, exuding disinterest or engaging in combative exchanges of chiselled sarcasm. Nothing is so terrible that you can’t make a joke about it, and snide comments are just another way in which we protect ourselves from baring our souls. London takes everything and nothing seriously, so oscillates between gaiety and aggression in a whirlwind of sniggering, shouting and rude remarks.

Our long late summer is finally fading into autumn. I love autumn. Every year, I get excited by the return of cold crisp air, and the brief rich colours of the trees. I never used to notice the shortening days (only the darkening mornings), but now that I run, this is autumn’s down side: getting used to running through the dark.