Simon Calder: The man who pays his way

Patagonia is prime territory for travel writers. Paul Theroux took a sequence of decrepit "express" trains to the bleak south of Argentina, while Bruce Chatwin wove fact, fiction and adventure to produce In Patagonia. I found myself there on Tuesday, and was entranced by the way the endless land collides so magnificently with the vast sky. But as I stared at the snow-capped Andes, ruminating about the rawness of life amid such austerity, the telephone rang. It was BBC Radio Five Live.

What, the producer wondered, did I make of reports that a nightclub in Brighton had banned anyone from Crawley? As the condors circled, I conducted a spirited on-air defence of Crawley, the town in which I was born.

Clearly, municipal envy lay behind the ban, I speculated: Brighton has little to offer visitors besides a spectacular royal palace, a thriving cultural life, and a prevailing air of Mediterranean indulgence. Crawley, meanwhile, possesses the busiest single- runway airport in the world. It is also the hub of Britain's travel industry, with everyone from Virgin Atlantic via Air Miles to First Choice planting their galactic HQs in the town.

How the nightclub proposes to ascertain whether a prospective clubber has arrived via the A23 isn't clear. But the story made me think about how your origins can seriously affect your travel plans.

The citizens of Bath, for example, have an edge over us lesser mortals, at least in the context of sightseeing in the city: they get free admission to the Roman baths and other attractions, and even a cut-price soak in the new spa.

In my experience, it is also worth taking your passport when out and about in Spain, because a number of museums grant free or reduced-rate access to EU- passport holders (though, if you carry your passport around Barcelona, there's a chance that someone else will help themselves to it).

Russia also shows favouritism to its citizens: locals typically pay one-third of the price to access the great palaces. Cuba has picked up the habit, too, with a twist: your nationality determines whether you pay a pittance in local currency to enter the Museum of the Revolution in Havana, or a tidy sum in "convertible pesos" (the ludicrous "hard currency" that tourists are obliged to procure, convertible nowhere but Cuba). Mind you, having a passport and freedom to travel is a priceless advantage that visitors have over most Cubans.

As for American citizens, their nationality precludes them from visiting neighbouring Cuba - or, more precisely, from spending money there. US Treasury rules designed to destroy Cuba's economy have patently failed, but Washington still forbids Americans from travelling to the Caribbean island.

Sir Richard Branson discovered that he had the wrong kind of passport when he tried to establish a low-cost airline in the US. Aviation law is strict about the nationality of airline owners, so Virgin America has been structured so that it is controlled by US investors: "We've had to cede control completely", Branson told me. Rival airlines are claiming this is not the case, and while lawsuits rumble on at the speed of the Old Patagonian Express, the airline remains grounded.

A British passport can be a boon, though. Today, a special supplement in The Traveller celebrates India, a nation accessible on charter flights from the UK - so long as you don't happen to be a citizen of the destination country. "Our Indian Licence doesn't permit sales to Indian nationals", says Thomson.

Bizarrely, the nationality of your fellow-passengers can affect you. Here's how. About a third of British Airways' business involves carrying transit passengers, most of whom change planes at Heathrow. Many are from countries whose nationals require visas to visit the UK, but they don't need paperwork as they are just changing planes. However, if flights are disrupted, BA may have to "land" them in a UK hotel overnight, which leads to legal complications that BA prefers to avoid. So, if a decision has to be made between operating, say, a Shanghai or a Seattle flight, passengers bound for China will probably win.

INDIAN TRAINS? AN ENIGMA

In this global age, location becomes ever-less important. For example, if for some strange reason you want to go from Crawley to Brighton, Indian call-centre workers will tell you the times of trains - the UK's National Rail Enquiries service routes many calls to the subcontinent. But finding out how to get from Poona to Patna by rail is an almost impossible task, even if you are already in India.

At one time, according to Thomas Cook, Southern Railway - just one of the 16 operating zones in India - "issued 27 timetables, all in different languages". At main railway stations in India, you can buy a marvellous book called Trains at a Glance - a bargain at 35 rupees (less than 50p) for anyone who loves planning imaginary journeys. But the chances of your actually finding the train you want "at a glance" are about the same as the Flying Scotsman entering service between Calcutta and Mumbai.

Even the index of stations is totally incomprehensible: page numbers are interspersed with train numbers, and can be decoded only with the help of a device as sophisticated as the Enigma machine. Still, it is the biggest transport undertaking in the world.