The Verdon Gorge ( French: Gorges du Verdon) is a river canyon located in the Provence-Alpes-Côte d'Azur region of Southeastern France. It is about 25 km (15.5 mi) long and up to 700 metres (0.4 mi) deep. It was formed by the Verdon River, which is named for its startling turquoise-green colour, one of the location's distinguishing characteristics. The most impressive part lies between the towns of Castellane and Moustiers-Sainte-Marie, where the river has cut a ravine to a depth of 700 meters through the limestone mass. At the end of the canyon, the Verdon flows into the artificial lake of Sainte-Croix-du-Verdon, named the Lac de Sainte-Croix.
As it is close to the French Riviera, the gorge is very popular with tourists, who can drive around its rim, rent kayaks to travel on the river or hike. The limestone walls, which are several hundreds of metres high, attract many rock climbers. It is considered an outstanding destination for multi-pitch climbing. The variety of 1,500 routes encompass cracks, pillars and seemingly endless walls, with a range in distance from 20 metres (65 feet) to over 400 metres (1,300 feet). The climbing is generally of a technical nature. It is often described as earth's second biggest canyon, after the Grand Canyon in the United States.  
During the Triassic period, the Provence subsided and was covered by the sea, leaving thick layers of various limestone deposits. Several million years later, with the arrival of the Jurassic period, the area was covered by a warm shallow sea, which allowed the growth of various Corals. The Cretaceous period saw what is now Basse Provence being raised and the sea reaching the current location of the Alps, which were themselves erected during the tertiary era. As a result of the large-scale geological activity, many of the Jurassic limestone deposits fractured, forming relief with valleys and other such features. The origins of the Verdon Gorge can be traced to this era.
The dawn of the Quaternary period had large-scale glaciation, transforming water pockets and lakes into unstoppable rivers of ice, which remodeled the topography, scouring and striating the landscape. At the end of this activity, erosion by rivers continued, forming the Gorge as it is today. The Verdon’s riverbed was scoured for a second time of the accumulated coral and limestone sediments, by a water delivery rate nearing 2000 to 3000 cubic metres per second.
The gorge was described in printed form from 1782 and 1804. By the second half of the 19th century, it was featured in French tourist guides. According to Graham Robb's book The Discovery of France, the gorge did not become known outside France until 1906.
On 10 July 2006, the Council of State annulled the declaration of public use of the Électricité de France's project, relating to a proposed high-voltage line carrying 400,000 volts, which would have had to pass through the Verdon Gorge. This decision ended 23 years of struggle by public groups and associations of environmental defence to preserve a site of exceptional natural interest, of which a part contains protected animal and plant species. 
The source of the Verdon is close to the col d'Allos hill in the Trois Eveches mountain range, whence it continues, flowing into the Durance river near Vinon-sur-Verdon after traveling 175 kilometres. Between Castellane and the Pont du Galetas, the river passes through the lac de Sainte-Croix, created by the construction of a dam of the same name. Before the dam was constructed, the village of Les Salles-sur-Verdon occupied the river plain. To create the dam and reservoir, the government forced the village to evacuate, dynamiting and destroying the church and other structures, before flooding the area in 1973. Les Salles-sur-Verdon was reconstructed as a more modern settlement higher up the valley. Today, it is the youngest village in France.
This region between Castellane and the Lac de Sainte-Croix is called the Gorges du Verdon, or Verdon Gorge. It is split into three distinct parts:
- “Prégorges” (‘pre-gorge’), from Castellane to Pont de Soleils,
- the deepest part of the Gorge, from Pont de Soleils to l'Imbut, and
- the Canyon from l’Imbut to the Pont de Galetas.
The Verdon Gorge is narrow and deep, with depths of 250 to 700 metres and widths of 6 to 100 metres at the level of the Verdon river. It is 200 to 1500 metres wide from one side of the Gorge to the other at the summits.
Between 1929 and 1975, five dams were erected on the course of the Verdon, between Castellane and Gréoux-les-Bains. These dams hold back water in the following reservoirs:
- Lac de Castillon, which was created by flooding the village of the same name
- Lac de Sainte-Croix, flooded the village of des Salles-sur-Verdon. Of note are the Roman bridge of pont de Garuby (or pont d’ Aiguines) and the “Bishop’s” spring at Bauduen. The lake has changing colours nearly every day and is a tourist destination, as well as the largest reservoir in France;
- Lac d'Esparron-Gréoux, known locally as “lac d’Esparron”. It is coloured green, like the Verdon.
- Reservoir at Chaudanne
- Reservoir at Quinson, sometimes improperly called the "lac de Montpezat", the name of the village over which it dominates.
The Imbut, also known as Embut or Embucq, is an area where the Verdon disappears underground, beneath enormous rock structures, before re-emerging above ground.
The Verdon Gorge is renowned as one of the most beautiful canyons in Europe,[ citation needed] and attracts numerous tourists, especially during the summer period. The river's striking turquoise colour is associated with glacial sources and the minerals of rock flour suspended in the water.
It is easily accessible on its right bank from the north (via route D952 from Castellane to Moustiers-Sainte-Marie), and on its left bank from the south (via routes D71, D90 and D955 from Aiguines to Castellane).
The southern route offers views of the Col d'Illoire, the summits of Plein Voir, le Pavillon (1624 m), la cime de Barbin (1560 m) and le Mourre de Chanier (1930 m), and the Saint-Croix reservoir. The "Sentier de l'Imbut" hike begins from this side of the gorge. Where the road passes through the Tunnel du Fayet, openings have been cut into the tunnel to afford a view to travelers. The road crosses the Artuby River over a bridge known as Pont de l'Artuby or Pont de Chaulière; soon after, at the relais de Balcon, the Artuby flows into the Verdon. This area is also known as the Mescla, meaning "mixture" in the Provençal dialect.
The D90 in the direction of Trigance passes over a bridge spanning the Jabron River (another tributary of the Verdon) and the Pont des Soleils. Just below Rougon is Couloir Samson (Samson's Corridor), the entrance to the part of the fluvial landscape designated as "gorge." From there one can hike along the Verdon and take the "Sentier Martel." La Palud-sur-Verdon, a village with museum and tourist bureau, is nearby; the "route des Crêtes" (Crest Route, linking various panoramic viewpoints) proceeds from here. The Sentier Martel also is accessible from this route, beginning at the French Alpine Club or "châlet de La Maline." This path covers more than 100 km of not always easy routes.
- The Verdon Gorge attracts many rock climbers for its more than 1,500 climbing routes on good limestone rock.[ citation needed]
- The Verdon and its Gorge are also a favoured destination for fishermen, particularly for fly fishing.
- Hiking, canoeing, paragliding, rafting, climbing and canyoning are some of the numerous sports practised in the region.
The most common hikes in the gorge include:
- Le sentier (pathway) de Martel
- Le sentier de l'Imbut
- Le sentier du Bastidon
- Le belvédère de Rancoumas par le pont de Tusset (the Rancoumas panoramic viewpoint near the Tusset Bridge)
The most famous of these, the Sentier Martel, was laid out in 1928 by the Touring Club de France. It was named in 1930 to honor the explorer Édouard-Alfred Martel (1859–1938). Martel had visited the Verdon in 1905 as an employee of the Southeast Electricity Company, carrying out precise geological surveys of the river. On 11 August, he and his team (explorer Armand Janet, schoolmaster Isidore Blanc, geographer Cuvelier, plaus Baptistin Flory, Fernand Honorat, Prosper Marcel, and Tessier Zurcher) began an expedition of the region by boat and foot (especially when one of the boats became unusable). They discovered a narrow corridor which Martel named "Styx". When they arrived at Imbut (meaning "narrow" or "funnel" in Provençal), Martel wanted to abandon the expedition, but his comrades encouraged him to continue. They entered the canyon proper and discovered more passages and rock formations; their successful arrival at the Pas de Galetas marked the completion of the first expedition of the Verdon Canyon.
Other expeditions to the Verdon included Martel's team the following year; followed by Robert de Joly, who in 1928 was the first to completely cross the Verdon Gorge, passing over the Imbut; explorer and filmmaker Albert Mahuzier in 1938 and 1939; a group of French Scouts in 1945; and the Canoe Club of France in 1946. Roger Verdegen made several expeditions along the Verdon in a boat made from animal hides and natural rubber, and became an authority on the river and its gorge.
From the chalet de la Maline to the Point Sublime, passing through Martel’s pathway with a detour via the Mescla.
The present-day Sentier Martel travels 15 kilometres (9.3 mi) along the right bank of the river Verdon from its entrance into the Canyon (Point Sublime) to the Châlet de la Maline. Some experienced hikers can do the round trip by foot in 12 to 13 hours; for those going one way, this section of the hike takes 7 to 8 hours with the detour via La Mescla.
Beginning at La Maline and going toward the canyon, the route descends in hairpins to join the water at the Estellié ford. Notable sights along this section include the Ravin de Charençon, the Pas d'Issabe, the Pré d'Issane (a small pebble beach along the Verdon), the Étroit des Cavaliers (a narrow passage between cliffs), the Guèges scree, and the large cave of Baume-aux-Boefus.
A detour allows one to visit la Mescla, where the Artuby river joins the Verdon, and where the Abbot Pascal, one of the Verdon's pioneers, drowned in 1928.
The main path towards the Point Sublime quickly ascends and comes to the Brèche Embert and its 6 stairways, totaling 252 steps (descending). Thereafter, the route climbs again along the Verdon, first very high above the riverbanks, then very close, to arrive at a pebble beach by the Baumes-Fères stream, near the cliff of l'Escalès.
The hike continues along the river bed, passing the Tours de Trescaïre on the other bank: two impressive monolithic pyramids. Then comes three tunnels: the Tunnel des Baumes, the Tunnel de Trescaïre, and the Tunnel du Baou, which were originally built for hydroelectric projects that were abandoned after World War II. Hikers wishing to explore these need pocket lamps and warm clothing; they range in length from 110 metres (360 ft) to 670 metres (2,200 ft).
At the end of the Tunnel de Trescaïre is a view of the narrowness of the Gorge, with the cliff walls of l'Escalès to the left and the rock face of l'Encastel to the right. Partway through the Tunnel du Baou there is a window hollowed through the rock that allows access to the Baume aux Pigeons, with a steep metal staircase leading to the river and its rock formations. After this last tunnel, the route goes beside the Verdon once more, then over the Baou to a new footbridge, leading back to the parking lots.
- Patriarca, Eliane. "Le Verdon sauvé des volts" (in French). libération.fr. Retrieved 17 March 2007.
|Wikimedia Commons has media related to Verdon Gorge.|