Five rivers.
Source to sea.
Each expedition traces a river from its mountain source to the open sea — combining hiking, kayaking, and cycling in any combination the terrain demands.
Use the menu above to jump straight to any expedition, or scroll through in order. Each section includes an interactive map — expand it for a closer look at the full route — alongside distance, elevation and more and the story of how each river unfolds from source to sea.
River Severn
The longest river in Great Britain, the Severn rises on the slopes of Plynlimon in the heart of mid-Wales and winds for 354km through Shrewsbury, Worcester, and Gloucester before reaching the Bristol Channel — one of the most dramatic tidal estuaries in the world.
The first Source2Sea expedition, completed in September 2025. Starting on foot from the source high on Plynlimon, the route transitions to kayak as the river widens, and finishes by bike along the estuary to the sea. A test of concept, fitness, and determination — and proof that the bigger expeditions ahead are possible.
The Severn is complete! Read the full account of how eight consecutive days actually unfolded — the flooding, the replanning, and the finish line.
River Severn: How It Unfolded →River Rhone
Rising from the Rhône Glacier high in the Swiss Alps, the Rhone descends through the Valais, broadens into Lake Geneva, then carves south through Lyon and Avignon before fanning out into the Camargue wetlands and reaching the Mediterranean Sea. At approximately 880km it is more than double the length of the Severn.
The first major international expedition — crossing two countries, passing through two mountain ranges, and finishing on one of Europe's great coastlines. Completed in September 2026, the route pushed into genuinely remote alpine terrain before the river became navigable, demanding a longer hiking approach than any expedition that came before it.
River Tagus
The longest river on the Iberian Peninsula, the Tagus rises in the mountains of eastern Spain and flows westward for over 1,000km through Toledo, the dramatic gorges of the Extremadura, and into Portugal — reaching the Atlantic at Lisbon, one of Europe's great river-mouth cities.
Planned for 2027, the Tagus crosses two countries and passes through landscapes that shift from high arid plateau to lush Atlantic coastline. The sheer variety of terrain — canyon, farmland, wetland, estuary — makes this one of the most visually dramatic expeditions in the series.
River Rhine
From its source in the Swiss Alps, the Rhine flows through Liechtenstein, Austria, and forms the border between France and Germany before continuing through the Netherlands and emptying into the North Sea — passing some of the most historically significant landscapes in Europe along the way.
At approximately 1,340km, this will be the longest Source2Sea expedition to date. Planned for 2028, the Rhine passes through multiple countries, time zones, and climates — presenting a logistical challenge unlike anything in the series so far.
Year 5
Route Coming Soon
The final expedition. Details to be revealed in due course.
The fifth and final Source2Sea expedition. The river and route are yet to be announced — but it will be a fitting conclusion to five years of adventure, fundraising, and purpose. What we can say: it lies beyond Europe, on a river close to 4,000km long.
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