London's afternoons are about to get darker a lot earlier. Every autumn, the UK switches off British Summer Time and returns to Greenwich Mean Time, moving clocks back one hour on the last Sunday of October. In practice, that means at 2am the clocks jump back to 1am, handing everyone an extra hour in bed but trading it for earlier sunsets — in London, dusk can arrive before 4pm by December.

For visitors, the date matters more than you might think. The switch affects everything from train timetables and opening hours to how much daylight you actually get for sightseeing. If you're in the city over the change weekend, double-check any bookings made for the early hours of Sunday morning — museums, tours and transport all run on the new time from the moment the clocks shift.

There's a practical upside too. This is the stretch of year when London does cosy best: pubs with roaring fires, Christmas lights switching on along Oxford Street and Regent Street from early November, and markets like Winter Wonderland in Hyde Park and the Southbank Centre's winter festival filling the dark evenings. Shorter days also make a strong case for indoor plans — the British Museum, Tate Modern and Borough Market don't care what time sunset is.

A bit of background: the idea of changing the clocks in Britain dates back over a century, introduced during the First World War to make better use of daylight. It's been debated ever since — Scotland's already-short winter days mean a clock change in the other direction would leave very dark mornings up north — but the twice-yearly ritual has stuck.

Why it matters for travellers: if you're planning a UK trip in late autumn or winter, come prepared for the light. Plan outdoor sights like parks, river walks and rooftop views for the morning, and save museums, galleries and pubs for after dark. And if you're flying in or out on the change weekend, remember the UK may be an hour out of sync with European countries for a week — the continent moves its clocks back a week later, which briefly scrambles flight and train connections across borders. Keep your phone on automatic time updates and you'll barely notice; it's the printed itineraries that catch people out.

Who's this for? Anyone visiting London between late October and spring who wants to make the most of limited daylight — and avoid the classic mistake of showing up for a 3pm walking tour just as the light is already fading.