BBC We’re already paying the highest ticket prices in Europe.

The claim: The UK has the most expensive train fares in Europe.

Reality Check verdict: The claim is based on very narrow research. The UK has some of the most expensive tickets in Europe if bought on the day of travel but some of the cheapest tickets if bought far enough in advance.

The Trades Union Congress (TUC) general secretary Frances O'Grady has said: "The last thing UK commuters need is another hefty fare increase. We're already paying the highest ticket prices in Europe."

The trade union umbrella body pointed us towards a few pieces of research to support this claim.

The first came from an organisation called Vouchercloud, which compared the price of a single ticket bought on the day of travel from a European capital city to somewhere about 50 miles (80km) away.

The UK (specifically the route from London to Oxford) did indeed come out as the most expensive - but is this a useful way to compare train fares?

First of all, we know buying tickets on the day of travel in the UK is expensive, so people tend to avoid it when they can. Commuters would be particularly likely to avoid doing so.

Also, UK train fares tend to be structured to make return train tickets only slightly more expensive than single tickets whereas in many other European countries they will be twice the price. Again, commuters would be particularly unlikely to buy a single ticket.

Comparing journeys

The TUC's other piece of research compared the price of a monthly ticket between Chelmsford and London and Manchester and Liverpool with similar journeys in France, Ireland, Germany and Belgium. And, once again, the commutes in England do indeed come out as the most expensive.

This is a more useful comparison but still not enough to conclude the UK has the most expensive fares in Europe - to do that you'd need to look at more than five countries and more than one or two routes for each.

Rail blogger Mark Smith, who runs the Man in Seat 61 website, wrote: "It makes no more sense to discuss rail fares all in one go than to discuss 'bus fares' without saying whether you mean National Express Victoria coach station to Leeds, or the number 13 from Baker Street to Oxford Circus."

He highlighted four European routes of about 250km.

And BBC Reality Check found the UK's was the second cheapest if booked a month in advance but the most expensive if booked on the day.

The cheapest single a month in advance:

London to Sheffield - £22

Paris to Dijon - £32.43

Rome to Florence - £20.06

Nuremberg to Kassel - £27.71

On the day:

London to Sheffield - £79

Paris to Dijon - £32.43

Rome to Florence - £46.33

Nuremberg to Kassel - £73.21

As Mark Smith points out, British train companies maximise revenue by selling tickets more cheaply ahead of time, when trains are emptier, in order to fill seats, and for much higher prices on the day.

This is partly because UK train companies get more of their money from passengers rather than through government subsidies.

Image copyright Getty Images

Other research

Comparing train fares overall is difficult because they vary so much depending on things such as how far in advance they are bought, what time of day passengers are travelling, whether they have a railcard of some sort and how far they are going.

The European Commission published a report in 2016 that compared different types of train fares.

The UK had the fourth most expensive regional, peak, single fares bought on the day of travel, behind Switzerland, Slovenia and Spain

It was the third most expensive if bought a week or a month in advance

For off-peak, return, regional fares it was 12th for on the day and 11th for a week or a month in advance

The UK had the most expensive inter-city fares for peak single tickets

For inter-city peak return tickets, it had the sixth most expensive tickets bought on the day, the second most expensive a week in advance and the dearest a month in advance

Another way of looking at it is by measuring the average revenue per train kilometre, used by the Rail Market Monitoring Scheme, another European Commission report.

It's a useful figure because it combines revenue from all sorts of tickets.

But how full the trains are makes a big difference to this figure, so it is very much influenced by the geography of a country and how good its train companies are at selling expensive tickets to those who can pay more and cheaper tickets to those who will not.

The UK comes out on top by this measure.

But there are other problems with it:

It includes non-ticket revenue from things such as catering and car parking

Changes in the average fare paid will not necessarily be the same as changes in the fares charged - it may just be that more people have decided to book in advance or more have needed to travel at the last minute

Trains v cars and buses

Because UK train travel is among the least subsidised by taxpayers, you would expect it to be among the most expensive in Europe.

Whether you fund a greater proportion of train travel through passengers fares or through general taxation is a political choice - and the UK has decided to go for the former.

Not everyone uses trains regularly. In Britain, 2% of all journeys and 9% of all miles covered are by train, compared with 61% of trips and 77% of miles by car. Buses account for 5% of journeys and 4% of miles.

The use of surface rail has risen by 40% since 2000, though.

Train travel in England is particularly concentrated in London (59 trips per person per year), the South East (24 trips) and the East (23 trips).

Residents of the North East took the fewest number of trips by train per person (four), followed by the South West and East Midlands (seven) and Yorkshire and the Humber (10).

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