Reserve an eight night walking trip in the Soca valley between May and September

Where the color comes from

A walking trip in the Soca valley is largely an argument about one color. The river runs from Trenta to the Italian border, and for the first fifty kilometers it is a green that photographs as fake and is not. The rock is limestone. Fine ground powder from the high catchment stays suspended in the water and scatters the short wavelengths back at you. Clear water plus rock flour gives you that particular green.

The channel does the rest. Below Bovec the river has cut narrow slots into pale stone, three or four meters across in places, polished smooth by everything it has carried. You can stand on the lip and look straight down eight meters to gravel.

Two things follow from the same fact. The water sits at eight to ten degrees Celsius in August, because most of it was snow six weeks earlier. And it is loud in a way that carries. You hear the Soca from the road long before the woodland opens up and shows it to you.

A front line at two thousand meters

From 1915 to 1917 this valley was the Isonzo front. Twelve battles were fought along the river, the last of them in October 1917, when Austro Hungarian and German units broke through at Kobarid and pushed the Italian army back to the Piave.

The evidence is still on the ground and nobody has tidied it. On the Kolovrat ridge above Tolmin the trench line is cut straight into limestone, with concrete gun positions, tunnelled shelters and iron pickets still standing in the grass. Krn, at 2,244 meters, was taken in a night attack in June 1915 and holds fortifications close to the summit.

Above Kobarid there is an Italian ossuary holding the remains of more than seven thousand men, most of them unidentified. The town museum holds the rest of the story, plainly presented and without much comfort in it. One walking day on this trip follows the marked route along the ridge. It is exposed the whole way and there is no water on it.

Kobarid to Tolmin on foot

The valley floor route runs about twenty kilometers between the two towns, and the trip walks it in a day with one short section on tarmac. It is not hard. Two hundred meters of climbing in total, most of it in the first hour.

The set pieces come early. The Napoleon bridge sits high over a slot in the rock north of Kobarid. Half an hour on is the Kozjak waterfall, which drops fifteen meters into a round chamber the water has hollowed out of the limestone, so the whole thing is lit from one side only. It is a five minute detour and everybody takes it.

Further down, the Tolmin gorges narrow to a few meters across, and a rock the size of a small car is jammed between the walls twenty meters up where a flood left it. The path is bolted to the side of the rock and wet all year. The handrails are there for a reason.

Count on rain, because the valley does

Bovec is one of the wettest inhabited places in Europe. The long term figure is around 2,700 millimeters a year, roughly four times what falls on London, and it arrives in short violent quantities rather than as drizzle.

The summer pattern is predictable and it still catches people out. Mornings are usually clear. By two in the afternoon cloud is building on the Kanin wall, and by four there is thunder somewhere in the basin. Ridge days therefore start early, and if the forecast is bad the guide moves the day, which means the itinerary you were given is a plan and not a promise.

Two other things. The river rises fast after a storm and the color goes from green to grey chalk for a day or two, so the photograph you came for may not be available on your dates. And from July the stretch below Bovec carries steady commercial river traffic from mid morning onward. If you want the quiet version of it, walk that section before nine.

Where $1,960 else goes

This departure sits on the $1,960 rung, and it is not alone there. The office keeps every trip at that figure on one page so the number can be seen doing different work in different parts of the world. It does not rank them and will not tell you which is the better buy, because that is not a judgement a figure supports.

• The whole of the $1,960 rung
• All eight figures side by side
• Every departure in one table