Col du Grand Saint-Bernard

Great St. Bernhard (Pass) "Until the Middle Ages"
Until the Middle Ages
Despite the great height, the pass has been walked since the early Iron Age, as is shown by finds along the access road in the north. At the time of the Roman Empire, it was one of the most important alpine crossings from Italy to Gaul and the Rhine provinces. The name of the mountain appears for the first time in Gaius Julius Caesar's report on the war in Gaul. Later other Roman and Greek authors such as Titus Livius and Strabo wrote about the pass road. Until it was expanded as a road under Emperor Claudius, there was only one mule track across the mountains. One advantage of the route was that there were no difficult-to-pass gorges at the entrances, such as the Gotthard Pass.
At the top of the pass there was a temple in Roman times, in which the native (Celtic) god Poeninus was worshiped, who was equated by the Romans with Iuppiter Optimus Maximus in the sense of the Interpretatio Romana. In the Middle Ages, the pass was still called Mont-Joux (from Latin mons Iovis).
The mountain crossing served secular and spiritual dignitaries, traders and crusaders, warbands and refugees as a route from the north to northern Italy and vice versa. It was a central section of a network of pilgrimage routes from the Franconian Empire and its successor states to Rome, which was bundled and then branched out again. These routes were known as Via francigena, German: Way out of the Franconian Empire. A good source for the route is the 994 travelogue of Archbishop Sigeric the Serious of Canterbury.
In the middle of the 11th century a hostel was built on the top of the pass. According to tradition, Bernhard von Aosta and Irmingard († 1057), the wife of the last Burgundian king Rudolf III, founded this institution on the border between the diocese of Sion and the diocese of Aosta. From this the Bernhardshospiz developed, from which the pass got its current name. It has been documented as a house of Augustinian canons since 1125. On the mountain, members of the hospice bred the St. Bernard dog breed, which proved itself as rescue dogs in the search for avalanche victims. She became known worldwide through Barry, who is said to have saved the lives of over 40 people.
Since the 11th century, the Alpine pass was under the control of the Counts of Savoy. As a connection between the Savoyard regions in the Lake Geneva region and south of the Alps, the route over the Great Saint Bernard with the hostel was important for the counts, dukes of Savoy since the 15th century. When the Valais conquered the Chablais and the Martigny area during the Burgundian Wars, the Savoy lost control of the northern foot of the pass road. Access from the north was via the Rhone bridge at Saint-Maurice, which led across the river at an easily controllable narrow point in the Rhone Valley, which was fortified with the Saint-Maurice Castle after the Burgundian Wars.
Modern times
On May 14th, 1800 Napoléon Bonaparte crossed the Alps here on his way to Italy. He also entrusted the canons of the Bernhard Pass with the hospice on the Simplon Pass.
In the 1850s, Switzerland and the Kingdom of Sardinia planned a winter-proof variant for the connection between the Val d'Entremont and the Aosta Valley. The Menouve Tunnel a few kilometers east of the summit of the Great St. Bernard Pass would have shortened the route significantly. Shortly after the construction work began, the project was abandoned again.
In 1905 a drivable road over the pass was completed.
From 1940 to the 1990s, the pass formed the south-western boundary point of the Swiss Reduit; the entrances in Entremont were secured against potential attackers by terrain obstacles and barriers; Artillery supported the blocked positions.
In the past, the path over the high mountain pass was only passable in summer. Since 1964, the road connection between the Valais and the Aosta Valley has led through the 5.85 km long, toll-based Grosser St. Bernhard tunnel and the historic pass road forms a detour to the hospice and through the beautiful mountain landscape. The Oléoduc du Rhône oil pipeline, which was closed in 2015, runs through the road tunnel from the port of Genoa to the Collombey refinery in Valais.
Text / Source: Wikipedia
de.wikipedia.org/wiki/Grosser_St._Bernhard

The austere buildings of the hospice of the Great Saint Bernard are located in a rocky pass through which an icy wind almost always blows, on the edge of a lake that is frozen on average 265 days a year and where winter lasts almost eight months. For nine centuries, canons regular of the order of St. Augustine, who settled here through the help of St. Bernard of Menthon, have maintained a tradition of helpfulness and hospitality. Travelers who want to relax for a while in that peaceful place are welcome all year round.

The Great St. Bernard has a lot of traffic on the lower section. On the last 500hm, the main road runs through the tunnel and the pass road is more varied and has little traffic.