Green traveller: Make tracks for Madrid on the Eurostar

I think it was the toothpaste that finally did it. The security man at Gatwick was deeply suspicious, because the tube of toothpaste that I'd stuffed into my computer case for my overnight stay in Strasbourg bore no indication of how many grams it contained. So how could he be sure that I wasn't about to contravene the anti-terrorism toothpaste regulations? It was as I waited for the airport's security bosses to reach a decision that I realised the joys of air travel were beginning to fade.

Compare and contrast: Waterloo International, ready to board the Eurostar. By force of habit, I had removed my laptop computer from its case to put it through the X-ray machine. "Next time, sir, there's no need to do that," said an official. No need? He was lucky I hadn't removed my belt and shoes as well, so inured have I become to the many indignities of airport security regulations.

Trains are to travel what slow food is to gastronomy. They restore an element of sanity to modern life; in other words, they recognise that speed is not necessarily the secret to happiness. And anyway, suppose you flew to Madrid from London: you would probably get an afternoon flight, have an indifferent dinner at your hotel, and then rise in time for a 10am meeting – which in Spain is the equivalent of the crack of dawn.

Take the train from London, on the other hand, and you board at Waterloo after lunch, connect in Paris with the appropriately named Trenhotel (train-hotel) in time for dinner on board and a good night's sleep in proper sheets with private loo and shower, and then arrive at your hotel the following morning in time for the same 10am meeting. So how much time have you really lost? Probably no more than a couple of hours.

As for stress, what stress? The security man at Waterloo was the last one I saw. My bag stayed with me at all times, my mobile phone was kept on throughout the journey (well, all right, that may not be altogether a good thing, but if I'd wanted to, I could of course have switched it off.) And while speeding through the French countryside as darkness fell, I ate decent food off china plates, with metal knives and forks, and drank excellent Rioja from glasses made of real glass.

To cross Paris from the Gare du Nord, where London trains arrive, to the Gare d'Austerlitz, from where the Trenhotel departs, I took the Metro. (You can buy Metro tickets at the Eurostar terminal at Waterloo, which means no hassle in Paris.) It takes no more than 30 minutes to make the transfer, although I allowed rather longer than that, just to be on the safe side. Even the Paris Metro can be susceptible to unexpected delays – in my case, it was a passager malade on the train precedent.

If you've persuaded a significant other to come with you, and you pay for gran clase (in which case your ticket includes dinner and breakfast on board), you get a two-berth compartment, with your own en suite facilities: a loo, wash basin, shower, towels, and toiletries. You get the same if you're travelling on your own, but it costs a bit more. For those with time to be touristy in Madrid, there is breathtaking art galore in three world-class art galleries – the Prado, the Thyssen-Bornemisza, and the Reina Sofia – enough designer clothes shops for even the most addicted of shopaholics, and easy day-trips to Segovia, Toledo and El Escorial.

I've been a fan of Channel Tunnel passenger trains since they started more than a decade ago. The journey is both civilised and comfortable, which is a lot more than can be said for flying. And Waterloo is several hundred times less ghastly than Heathrow or Gatwick. I am now equally a fan of the Paris-Madrid Trenhotel. (Renfe, the Spanish railway enterprise, also does Paris-Barcelona.) Admittedly, they no longer hoist the whole train aloft when it gets to the French-Spanish border so that they can change the bogies (French and Spanish rail gauges are different), which is what they did the last time I made the trip by rail, more than 30 years ago. Now there are just a few bumps and clunks at the border as they do something clever with the wheels.

If you insist on working while you travel, there are power points for your laptop and phone charger. So, if you're really organised, you can have the report on your trip written up and completed by the time you get back to Waterloo. I'd all but finished writing this on the train back from Paris to London, and we hadn't even reached Britain.

Now, if only they'd build a tunnel under the Atlantic.

Robin Lustig presents 'The World Tonight' on BBC Radio 4

Park life: what to see

Parque del Retiro

This sprawling green space is the largest in central Madrid, pushing out north-east from Atocha railway station. The park was built for King Philip IV and today is much cherished by Madrileños, who sit in the shade of its horse-chestnut trees on hot summer days or cycle along its pathways. Around the same size as London's Hyde Park, it encompasses manicured lawns and flower beds, fountains, a Japanese garden, observatory and small artificial boating lake.

Atocha Railway Station

While Atocha was Madrid's first railway station (built over 150 years ago), it is better known nowadays for its distinctive indoor garden, embedded in the heart of the old station (now a concourse peppered with shops and cafés). With 4,000 square metres of tropical flora, it has become a destination in itself. More than 500 species inhabit the garden, as well as goldfish and turtles in its pond feature. This unique attribute gives character to what, at first glance, appears to be a busy commuter station.

Faunia

This ecological theme park on the eastern outskirts of the city allows visitors to appreciate wildlife in the next best thing to its natural habitat. The park's eight eco-systems recreate climates from around the globe, from tropical rainforest to desert via the polar-regions. For example, the Amazon Jungle houses hundreds of tropical birds and small reptiles. There are more than 1,500 animals within the park, some of which are free to roam and interact with visitors, making for a unique wildlife experience (00 34 91 301 6210; www.faunia.es).

Real Jardin Botanico (Botanic Gardens)

Situated on the Paseo del Prado, the Royal Botanic Gardens was created by King Charles III in the 18th century as a space to develop herbal remedies and house species collected from Spanish colonies across the globe. Today, the diverse 30,000-plus plants originate from as far afield as Japan, arranged in beds, hothouses and pavilions. The Exhibition Greenhouse is also an important research facility, dedicated to maintaining the ecosystem of this part of the world (00 34 91 420 30 17; www.rjb.csic.es).

Casa de Campo

The largest of Madrid's green spaces, Casa de Campo feels more rural than its central counterparts. The sprawling parkland snakes around the west of the city and is home to an outdoor pool, a zoo and a fairground. Those with a head for heights can get a bird's eye view of the park and a unique vista of the city from the cable cars that soar above the tree canopy.

Adam Hamadache