Slow tourism has become one of 2026’s defining travel trends, with more than seven in 10 travellers now saying it’s important to minimise their environmental impact while on holiday.
Rail fits that brief perfectly, offering lower emissions than flying and the simple pleasure of watching the landscape change outside your window rather than rushing through airports. Tapping into this shift, flight-free travel platform Byway has launched a 15-day itinerary built around the Douro Line, spanning across not one but three countries making it one of Europe’s most scenic railway routes.
A 15-day, flight-free train journey from London to Portugal’s Douro Valley
The journey begins at London St Pancras, where you board a Eurostar to Paris Gare du Nord and roll out past Kentish fields before emerging into classic French countryside. From Paris, a connecting train whisks you south to Nîmes, nicknamed the “French Rome” thanks to its beautifully preserved Roman arena and temple, the Maison Carrée, where you spend two nights. This is the first taste of the trip’s rhythm: unhurried daytime rail legs punctuated by two or three-night stays in cities you might otherwise only pass through.
Next comes a six-and-a-half-hour rail hop from Nîmes to Madrid, Spain’s capital, where two nights give time for the blockbuster sights: Europe’s largest royal palace and heavyweight art museums including the Prado, Reina Sofía and Thyssen-Bornemisza. Just 90 minutes further along the tracks lies Salamanca, a lively university city whose UNESCO-listed old town is packed with grand architecture like the Plaza Mayor, twin cathedrals and a Roman bridge, and you settle in here for another two days.
Portugal’s Douro Line – Porto to the UNESCO World Heritage wine region
From Salamanca, the route switches briefly to road, with a bus carrying you across the border to Porto, Portugal’s atmospheric second city, where three nights are included. Porto’s medieval riverside centre is itself a UNESCO World Heritage Site, all colourful façades, church towers and a waterfront lined with cafés, wine lodges and traditional boats. Book lovers can seek out what’s often dubbed one of the world’s prettiest bookshops, while food and wine fans are spoiled with port cellars and hearty northern Portuguese cooking.
Then comes the main event: the Douro Line between Porto and Pocinho, a rural village set amid steep, terraced vineyards in the upper Douro Valley. This scenic railway traces the curves of the Douro River through a landscape that is both a UNESCO World Heritage wine region and the historic birthplace of port, with trains threading past quintas, tiny stations and dramatic hillsides. It is this stretch – slow, winding and wildly photogenic that cements the route’s “spectacular” status and makes the longer overland journey from the UK feel worthwhile.
What it costs for the 15-day, flight-free train journey from London to Portugal wine region
A flight-free holiday doesn’t end until you arrive home, and the return leg keeps you on the rails through Spain and France all the way back to London. On the way, you call at Vigo, a lively port city in Galicia, before continuing north through France and eventually back under the Channel to St Pancras. Taken together, the package spans three countries and eight cities across 15 days, with accommodation and almost all rail travel bundled in.
Prices start from £1,595 per person, which the operator frames as good value once you factor in the length of the trip, number of stops and the included hotels and tickets.
The itinerary also claims up to 71% lower emissions compared with flying, giving travellers a way to indulge in a big European escape while significantly shrinking their carbon footprint.
For those who get hooked on rail, similar London-to-Portugal journeys can also take you to Lisbon, Faro or the Algarve via Eurostar to Paris and high-speed links through Barcelona, Madrid or Seville, albeit with extra changes and an overnight stop.
For anyone who loves the idea of making the journey part of the holiday, the combination of big-hitting cities, smaller characterful stops and a finale on the Douro Line makes this one of 2026’s standout rail trips.