The Liberal Democrat Party has revealed new figures showing the huge disparity in costs between different train operating companies.
It follows a recent report from the Rail Passengers Council, which claimed that the opportunity to purchase cheaper rail tickets is simply not given to many rail passengers.
Among the findings was the fact that with a standard saver return ticket costing £10 would take you almost 70 per cent further on the cheapest operator (Wessex Trains - 36 miles) than the most expensive (South West Trains - 22 miles).
The Liberal Democrat shadow transport secretary, John Thurso, said: "These figures reveal the stark fact that there is absolutely no consistency in prices between the different parts of Britain's rail network. Some rail passengers are effectively paying twice as much as those using other lines."
The Heathrow Express works out to be the most expensive operator, when taken with an open return ticket taking passengers only six miles for £10.
On average, open return fares are in fact twice as expensive as saver return fares. For £10 the latter is able to take passengers 12 miles further than open return tickets (29 miles compared with 17 miles).
Mr Thurso added: "If the aim is to get more people onto public transport, ministers must address why we have such high and uneven pricing in Britain."
He concluded: "The current system is clearly unfair to a large number of passengers and could well be a major factor in people's reluctance to switch from using their cars."
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