The nineteenth-century Salbertrand Ice House, one of the few natural ice houses (building and adjoining supply lake) left intact in Piedmont, was in the past an important resource for mountain dwellers, also considering the seasonal nature of the work, complementary to the agricultural one.
At the beginning of the 1900s, some traders from Oulx, united in a company, built the icehouse building to store the ice produced in winter in the adjacent artificial lake.
By taking advantage of the difference in height between the bed of the Rio Gorge and the edge of the lake, a room of 800 m3 was created which, with the carrying of some embankments outside, was almost completely underground. To defend the structure from the summer heat, a layer of about one meter of earth was brought back on which Scots pines were planted.
A smaller stone construction, placed against the front facade of the building and delimited by two wooden doors, constituted an efficient compass entrance which ensured the cold was kept in the icebox and served the carters as protection from the rain.
A wooden slide placed inside a gully (culìs) dug along the slope between the lake and the ice house was used to transfer the blocks.
Three windows, positioned at different heights, were used for storing and removing ice.
An internal system of wooden scaffolding had the purpose of slowing down the travel of the block coming from the outside, accompanying it along the descent, avoiding its breaking.
At the time of sale, the blocks of ice wrapped in wet jute sheets were placed on two-wheeled carts and taken to the railway station. Most of the product was loaded onto trains and sent to Turin, a small quantity went towards the Upper Valley, for the first places frequented by tourists, and, sometimes, up to Briançon.
At the time of greatest activity, between the beginning of the twentieth century and the First World War, the icebox was emptied annually. When, with the appearance of refrigeration machines, factories were built to produce ice directly in the places of greatest consumption, natural ice houses were almost completely abandoned.
In the last year of activity, the production of the Gran Bosco icebox remained unsold and was stored until the following winter, demonstrating the perfect thermal insulation of the construction.