Day trips from London, ranked by whether they're worth the day

Every London itinerary eventually hits the same question: should we take a day out of the city? The honest answer is usually no. London has more than most people can see in a week, and a day trip costs you the day plus three hours of travel plus the mental overhead of trains.

But some of them earn it. Here is which, and why.

The six, side by side

Bath — the one that justifies the day

Two hours forty-five minutes of return travel for a city built entirely out of the same honey-coloured stone, wrapped around a Roman bathing complex that has been in continuous use since the first century. It doesn't look like anywhere else in Britain, which is the whole point of leaving London.

The Roman Baths cost £29 on a weekday and £33 at weekends when booked in advance — tickets bought on the door are £2 more. It's a genuinely good museum, and the audio guide is one of the better ones in the country.

Do the Baths in the morning, walk the Royal Crescent and the Circus, eat, and get an afternoon train back. You will not feel you rushed it.

One warning: the Thermae Bath Spa, where you can actually get in the water, is a separate business and books out weeks ahead. If that's the appeal, book before you book the train.

Oxford and Cambridge — pick one, go for half a day

They are more alike than either would admit: an old university, honey stone or pale stone, colleges you pay a few pounds each to enter, a river with punts on it, and a lot of other tourists.

Oxford is marginally easier to reach and denser to walk. Cambridge has the better single view, the Backs, and better punting. Whichever you choose, the other adds almost nothing.

Go in the morning, see two or three colleges rather than seven, have lunch, come back. A full day is more than either needs unless you have a personal reason to be there.

Check college opening before you travel. They close for exams, ceremonies and conferences with little notice, and Christ Church in Oxford — the one people go for — is often the first to shut.

Brighton — a genuinely different day, in summer

Britain's most cheerful seaside city, an hour from Victoria. The Lanes are good for browsing, the Royal Pavilion is a properly strange building, and the sea is right there.

The catch is weather. Brighton in July is one of the best days out in England. Brighton in drizzling February is a windy grey seafront and a lot of closed things. This one is entirely seasonal, and the pebble beach surprises people who were expecting sand.

Windsor — the one to skip

Windsor Castle is the most-booked day trip from London and the one we'd cut. It costs £32 booked ahead, or £36 on the door. It's forty minutes away, which makes it easy, and that ease is most of its appeal.

But you already have the Tower of London — older, stranger, more interesting, and inside the city. Kensington Palace and Hampton Court are both royal residences reachable without leaving your travelcard. Windsor gives you a fourth version of a thing London already does better, plus a train.

If you're going anyway: book in advance to save £4 a head, and check whether the State Apartments are open on your date. They close for official events, and without them the ticket is poor value.

Canterbury — the underrated one

An hour from St Pancras on the high-speed line, and almost nobody on a first London trip considers it. A medieval city small enough to walk end to end in twenty minutes, with a cathedral that is one of the genuinely great buildings in England and a thousand years of pilgrimage history attached to it.

If you've already done Bath, or you want somewhere that isn't full of other day trippers, this is the one.

How to not overpay for the train

This is where most people lose money, and it's the easiest thing to fix.

Advance singles are dramatically cheaper than walk-up fares. They're tied to one specific train, they're non-refundable, and they go on sale roughly eight to ten weeks before travel. On short routes the saving is often half; on long ones it can be eighty per cent.

Two singles usually beat a return. Britain's fare system rewards booking each leg separately more often than not. Always check both.

Avoid the weekday evening peak out of London. Off-peak tickets are typically invalid on trains leaving London between about 15:00 and 19:00 Monday to Friday. Coming back at 18:15 can cost more than the entire rest of the day.

Weekends are simpler. Off-peak rules generally don't apply, so a Saturday trip is easier to book cheaply on the day.

Buy direct from the train operator or National Rail rather than a reseller, and be wary of booking fees.