George Osborne was forced to pay for an upgrade after sitting in a first-class train carriage with a standard-class ticket.

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On its website, Virgin Trains warns travellers they will be charged an excess or penalty fare if they board a train without a ticket or attempt to change from standard to first class without a first class ticket.

BBC: George Osborne

Furthermore, intrepid visitors looking to climb Huayna Picchu the prominent peak towering over the site, and the crown of Machu Picchu , must purchase a separate ticket along with their general site admission for a total of 150 soles, which includes standard access to the Machu Picchu site.

BBC: Securing tickets for Machu Picchu