Canyoning in the Alps. Simon Flower

Even so, a number of companies had questionable standards and poor safety records. In 1999 the sport gained notoriety following the tragic deaths of 18 paying tourists (mainly Australian) and three guides during a flood-pulse in Saxetenbach Gorge, near Interlaken.

      Val Zemola (Route 66 in the Friuli Dolomites), one of Italy’s most famous canyons, was first descended in 1986

      The present day

      Canyoning ethos in western Europe has shifted firmly from exploration to sport. Certainly, in France and Spain it seems unlikely that any great surprises lie in wait. Both countries have been thoroughly scoured for canyons and the more notable finds published in guidebooks or websites. Elsewhere, canyon details have taken longer to filter through to the wider canyoning community – northern Italy was virtually terra incognita until the first guidebooks emerged at the turn of the 21st century, and central Switzerland appeared on the map only in the last couple of years.

      Undoubtedly, there is still more to be found. Of the areas in this guide, Carnia and the Julian Alps hold perhaps the greatest potential, yielding three classic descents during the time this book was written.

      Outside Europe, away from the US, Australia and the French and Spanish overseas territories, there is enormous opportunity for making first descents. There are few places on the Earth’s surface that remain as little known as canyons. Even in New Zealand, with its thriving outdoor community and majestic, canyon-rich mountain scenery, the sport has only just taken off. Travel to Asia, South America or almost any other mountainous land you can think of and the canyons are there for the taking. Pack your flags and get out there!

Geology of the Alps (for canyoners)

      A brief history of the Alps

      The Alps, like all great mountain ranges, were created by the collision of continents. They began rising some 90 million yeas ago as Italy, inching slowly northwards, collided with the southern edge of mainland Europe. The ocean floor that once divided the two continents gradually disappeared, driven into the Earth’s mantle as the gap between them closed. As the land masses collided, their margins buckled, folded and slid over each other to form immense overlapping thrust sheets, or nappes, which pushed northwards as Italy continued to advance. In this way, great rock masses from the Italian plate were displaced far to the north to create mountains in what are now Switzerland, Austria and France. As the Alps rose, the rocks of the ancient seabed were exhumed, now metamorphosised by the immense heat and pressure of the Earth’s interior. Today these hard-wearing metamorphic rocks (the so-called Penninic nappes) form much of the backbone of the Western Alps.

      Beautifully shaped gneiss in Massaschluct (Route 1 in the Valais Alps)

      Canyon formation

      Although plate tectonics are responsible for the formation of the Alps and the distribution of its rock types, the rugged landscape seen today is largely due to glaciation. Over the last two million years there have been a number of periods of glacial advance and retreat that have done much to remodel the region. The last glacial period ended some 10,000 years ago, when the climate changed so quickly that the glaciers retreated into the mountains over only a few hundred years – a mere blink of an eye in geological terms. Colossal sheets of ice were set in motion across the mountains, scouring deep channels into the rock and forming conduits for billions of tons of melt-water – the canyons we see today.

      Limestone environments are susceptible to another, more subtle process – karstification. Limestone is one of the few rocks soluble in rainwater (a weak acid), and it gradually dissolves over time to form a number of characteristic landforms, including caves, dissected plateaus and deep slot canyons.

      The regions and their rock types

      The canyons of Val d’Ossola, Ticino and the north-western shores of Lake Como are for the most part formed in gneiss, a highly metamorphic rock of the Penninic nappes. At extremes of temperature and pressure within the Earth’s interior, minerals of a similar type within the parent rock (here mainly granite) have migrated and aligned together. This gives the rock a beautiful decorative quality with swirls and bands of different colours, polished smooth by the action of glaciers and flowing water. These canyons are often sporting, with deep green pools and gently sculpted waterfalls ideal for jumps and toboggans.

      Impressive limestone scenery in Rio Simon (Route 85 in the Julian Alps)

      The area around Lake Como is geologically complex, and gneiss is only one of a number of rock types in the area. Valtellina, a broad valley extending east from the northern tip of the lake, is part of a long fault line – a weak point in the Earth’s crust – that runs east–west across the Alps. The fault, known as the Insubric Line, marks the boundary between the Italian and European plates. This weakness has allowed liquid magma to ascend from beneath, cooling slowly within the Earth’s crust to form coarse-grained rocks such as granite and diorite. These have been exposed in a number of places along the fault, creating some of the youngest mountains in the Alps. Among these is Piz Badile, a granite peak on the Swiss border, where a couple of canyons reside. Although granite is hard it erodes quickly on account of its grainy structure, leaving well-rounded canyons open to sunlight.

      Just east of Piz Badile is Piz Bernina, one of the most celebrated mountaineering peaks in the eastern Alps. Its southern slopes are formed of a distinct grouping of rocks that includes basalt, gabbro and serpentinite. These rocky assemblages are common throughout the Alps. Termed ‘ophiolites’ in the early 19th century (a word derived from the Greek for snake-stone), it would be another 100 years before their significance was understood. They are now believed to be fragments of the ancient ocean crust, scraped off as they dipped beneath the advancing Italian plate. Serpentinite, derived from the deepest layer, is the most significant from a canyoner’s perspective. It has a mottled greenish tinge and waxy polished surfaces similar to soapstone (to which it is closely related). Serpentinite canyons are extremely rare. Perhaps the best known is Cormor on the flanks of Piz Bernina, famous for its sculpted cave-like passages, almost totally devoid of light. There is nowhere else in Europe like it.

      To the south of the Insubric Line, from Lake Como to Slovenia, lie the Southern Limestone Alps, home to the limestone areas described in this guide. All limestone (and dolomite) in the Alps originated in the ancient seas that once separated Italy and Europe. It is formed from calcium-rich minerals mainly derived from the shells of marine organisms laid down throughout the Mesozoic Era (the ‘Age of the Dinosaurs’ – around 65–250 million years ago). Owing to the solubility of limestone in rainwater, limestone canyons tend to be narrow, twisting and deeply encased, resembling cave passages open to sunlight. Like their subterranean counterparts, karst features such as stalactites, flowstone and rock arches are common. Distinct bands are often visible on the canyon walls, each representing a different age of limestone formation, although the banding is now rarely horizontal owing to folding and buckling of the Earth’s crust. Older layers underlie more recent ones, and a descent through a limestone canyon may take you through several million years of Earth’s history.

Weather and when to go

      Water levels in a canyon are a reflection of weather conditions (chiefly rain, snow and temperature) over the preceding weeks to months. Ideally, it would be possible to plan a holiday when water levels are sensible (or not so sensible, depending on your persuasion) during periods of fine, settled weather. Unfortunately, predicting both water levels and the likelihood of having good weather is difficult, as the weather conditions in any given month differ dramatically from one year to the next. For example, a snowy winter or a wet spring will mean water levels remain elevated in summer, even if the summer is hot and stable. In other years, the spring months will be dry and canyoning perfectly feasible. Recommending when to visit is therefore a little tricky, and the advice given here must