The Royal Family clocked up more than £5 million in travel bills last year - including £500,000 on a single trip to Latin America taken by Prince Charles and the Duchess of Cornwall.
The £5.1 million bill includes £100,000 for Prince Harry's trip to Brazil and Chile, where he visited underprivileged children and the military, as well as attending the World Cup. However, he and Prince William made most of their journeys by charter flight, keeping costs down.
One exception was Prince William's trip to China and Japan, which cost £70,000 - as well as another £20,000 on 'reconnaissance flights'.
Charles, though, made 17 trips costing more than £10,000 each, and spent 14% more than in the previous year: over £1.5 million in all. His trip to Colombia and Mexico with Camilla cost £446,159, and a five-day visit to the Middle East last February came in at £262,212.
The carbon footprint of the prince, well-known for his interest in environmental issues - shot up by more than 40%. However, Clarence House points out that most of Charles's travel was on official business that he had taken over from the Queen.
The royal train made 13 journeys costing over £10,000 - including one 140-mile trip from London Euston to Wolverhampton made by the Queen and the Duke of Edinburgh, which cost £15,956 - around £114 a mile.
The £5.1 million travel bill is up by a fifth on the previous year. And while 2013 saw the royals making 47 trips costing £10,000 or more, last year that figure shot up to 63.
Anti-monarchy campaign group Republic says its research shows that the Royal Family costs the British taxpayer £333.9 million in all - eight times the official figure. Unlike official reports, it includes direct expenditure on items such as security, lost income and lost opportunities to raise revenue.
"With this kind of money we could be employing 15,000 new nurses or 14,000 new police officers. Instead we're flying royals around by helicopter and paying them multi-million pound incomes from the Duchies," says Republic CEO Graham Smith.
"The palace's claim that they only cost each person 56p is just bad spin - would MPs get away with claiming their proposed pay rise will only cost us 7p per person?"
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