For her summer holiday this year, Anna Hughes, 36, is cycling from London to Nice, stopping in Paris, Nevers, Lyon, and Provence along the 700-mile route. To return, she’s jumping on the TGV in Nice, arriving back in London around nine hours later. Hughes is one of the trailblazers for flight-free holidays, avoiding gas-guzzling planes for the past decade, and is now director of Flight Free UK, a campaign group encouraging people to take a no-fly year in 2020.

“I don’t fly because it’s about the worst thing an individual can do for the environment,” says Hughes. “Even if you take other steps to be environmentally friendly, like recycling everything, using green energy, or even becoming vegan, one flight can wipe out all your savings. A flight is pretty much the most carbon-heavy thing you can buy.”

A long-haul flight produces more emissions than the average person generates in a whole year

According to recent Guardian analysis, a long-haul flight produces more carbon emissions than the average person in dozens of countries around the world generates in a whole year. Travelling by train or ferry is significantly kinder to the environment: for instance, the Eurostar from London to Paris produces 4.1kg CO 2 per passenger per person compared to 63.6kg by flying, according to the high-speed rail service.

In the face of a climate emergency, increasing numbers of people are chosing to ditch planes. While there are legitimate concerns about the additional time and cost, travelling by train to some parts of Europe can end up being a similar price to flying (and minus the headache of hanging around at the airport). Take Hughes’s rail journey from Nice to London, which cost £102. The cheapest one-way flights we could find for an August weekend were £140, although they drop to between £60 and £80 in September.

On a return trip from London to Dublin earlier this year, Hughes travelled on a one-way Rail & Sail train and ferry ticket that cost her £50. Looking at prices for next week, Guardian Money found that leaving London at midday and arriving at Dublin Ferry port at 7pm costs around £43.50 for departures scheduled during next week. The cheapest equivalent flights to Dublin are selling at about £45 one way, without the typical £10 to £20 cost to get to the airport.

“I live in London and that’s an easy transport hub, but given the extra costs of airport transfers, going to Dublin by train was cheaper than flying. People think flying is cheaper, but it isn’t always,” says Hughes.

While flights at off-peak times are generally cheaper than trains, it is often the case that travelling at peak holiday times is cheaper by train.

There’s also the added benefit of saving on expensive airport transfers. A peak and off-peak express train from Heathrow to Paddington costs £25 each way, while a return is £37. A single standard ticket from Liverpool Street station to Stansted is £18.90; a standard return is £29.90.

Facebook Twitter Pinterest The tiled interior of the recently restored São Bento railway station in Porto, Portugal. Photograph: Jeff Greenberg/Universal Images Group via Getty Images

However, London is, of course, a much easier transport hub than most other parts of the UK, meaning people living outside the capital would have to consider the price of train tickets if travelling on Eurostar. However, no matter where we’re located in the UK, most fliers are burdened by the extra fees.

Ryanair charges £25 to £35 to check in a 20kg bag on a one-way flight. When Guardian Money looked to book an EasyJet return flight from London Gatwick to Madrid for August, the original price came in at £54.79, but eventually rose to £93.77 when including a £19.49 fee for 23kg of baggage each way. And that’s not all. Want to choose where you’ll sit on an EasyJet flight? That’ll be £8.49, thank you.

For their summer holiday this year, Abigail Thomas, 37, producer and co-presenter of The Hopeful Activists’ Podcast, and her husband and three children aged eight, six and four, are travelling by train to Switzerland. They say it will cost a little more, but they are having a very different experience. “Our children are becoming passionate about the environment through their school so it seemed a natural step,” says Thomas, who lives in Bradford.

She outlines the cost implications: “We’re using an Interrail pass for our train travel on the continent, which will cost €575 (£515) as you get two children free on each pass. Our Eurostar tickets, discounted by the pass, are an additional £265.”

The family also plans to make pit-stops in Brussels and Basel. “We could have had a package holiday cheaper if we were flying, but doing it this way we have a much more interesting holiday.”

Mark Smith, founder of the train ticketing information site Seat61.com, believes taking the train to parts of Europe is on the verge of becoming mainstream. “This is a grass-roots movement – it’s not coming from the travel industry, which is set up to book flights, car hire and more flights and would rather people flew.

“Nor is it coming from the rail industry, which needs to work together more to facilitate this if they want to benefit fully in terms of easy booking systems, and passenger rights when delays mean a missed connection.”

Despite the lack of coordination, he says travelling by train can be affordable. “They have their cheap fares if you book in advance at the right website. For example, you can travel from London to Paris from £58 return, Paris to Venice from €29, or London to Berlin from £69.90.”

There are also plenty of offers at Rail & Sail, which combines train and ferry travel in one ticket. StenaLine offers ferry and rail trips such as Harwich in Essex to any Dutch station from £49 one-way for an adult and £24.50 for a child. Guardian Money found a Manchester Victoria to Dublin Ferryport ticket, taking five hours 53 minutes door to door, for £39.50. Alexandra Jellicoe, 41, who lives in Bath and is an environmental scientist and blogger at Monkey Wrench, is one of the 2,000 people to have so far signed up to the Flight Free UK campaign. She admits she was a frequent flier up until April this year when she started feeling uncomfortable about the amount of air miles she was racking up.

“I was aware that climate change was a big problem, and I was doing my best at home to lead an eco-conscious lifestyle. But I have always lived abroad and travelled extensively for work and leisure, so flying was a fixed part of my routine.

“We’d got stuck in a routine of hopping on a cheap flight from Bristol and limited ourselves to places we could access from there.”

UK train operators reverse decision to quit Interrail Read more

This summer the family of five – husband Matt and three children aged seven and under – will take the train to Annecy in France, in a trip costing £1,171 and booked through train booking platform Loco2.

Jellicoe says a return flight from Bristol to Geneva at the same time, plus connections to the airport at each end, would have cost £1,154. “When you start to think about carbon emissions as part of your decision-making process, you start to travel in different ways – where can I get to by train and which routes are easiest and cheapest.

“It’s a different set of limitations but equally exciting. Rather than a weekend, or a week here or there, we’ll plan to go for two to four weeks. And if we only have a short time we’ll holiday closer to home.”

Jasmine Salter, 27, based between London and Scotland, used to fly three to four times a year but has radically changed since listening to an Extinction Rebellion talk in November last year.

“I haven’t flown since,” says Salter, who volunteers full-time for Extinction Rebellion. Instead she’s choosing the bus and hitchhiking. Recent trips include a 24-hour bus to Geneva at about £40 with an overnight stop at a hostel in Paris for £17. “The difference is how long it takes which makes enjoying the journey part of the adventure,” says Salter. “There has to be a change in the way we value things.”