There are many reasons why train travel trumps flying - from the lack of officious security personnel to the fact that travellers are deposited in the heart of the city, rather than the outskirts of Staines. It's also far better for the environment than journeys by plane or car.

But which countries have the most extensive rail networks, offering the best chance to explore them without boarding a flight or sitting for hours on the motorway?

The map above shows the world's nations according to their railways. Those shown in dark blue have the most extensive networks, those in lighter colours the smallest. Those in grey either possess no railway or have not returned figures. Unsurprisingly, the largest and most populous countries dominate, with the USA, China, Russia, India and Canada making up the top five.

10 countries with the most railways

USA China Russia India Canada Germany Australia Argentina South Africa France

There are some more surprising findings, however. The British attachment to rail travel is clear. It has the world's 17th largest rail network, at 17,732km, despite being just the 78th largest nation by land area. That figure was once as high as 34,000km.

Romania's rail network is surprisingly extensive

Romania's 22,298km network is also impressive, putting it 15th on the list, even though it is only the world's 81st largest country.

Conversely, several of the world's larger countries (by land area) have almost no rail connections, such as Mali, Madagascar and Afghanistan. Paraguay, by no means a microstate with a population of seven million, has just 38km. Laos, which covers 236,800km² and is home to 6.8m citizens, a mere 3.5km. And the smallest of all? The Vatican City, with a tiny 1.27km line.

Fancy exploring Iceland by rail? Well you can't

Many more destinations don't have any railways, often due to the harsh, mountainous or densely forested surroundings. They include Iceland, Greenland, Yemen, Oman, Bhutan, Libya and Papua New Guinea.

11 destinations with no railways at all

Iceland Greenland Yemen Oman Bhutan Libya Papua New Guinea Chad Cyprus East Timor Nicaragua

For more on the world's greatest train journeys, check out our expert guide.

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