Located right at the centre of a geological zone called Bacino Terziario Piermontese, the Langhe hills still keep their original shape which was formed 35 million years ago.
During the Miocene period layers of sand, marls and clay made up a sediment in the sea, which was slowly but steadily sinking.

Some millions of years later, during the Pliocene, when the sea receded, those layers of land emerged and have been gradually shaped by climatic events since then.
The finest of those sediments formed the thick layers of bluish marls called “tufi”, where fossils are still to be found today.
The sandy layers of silt were formed by undersea movements sucking back a mass of material from the coastline.

The soil is thus made up of a deep Miocene layer of calcareous marls. The percentages of clay, silt and sand vary from place to place, depending on the sedimentation which has taken place over time.

In La Morra the soil is made up of about 20-40% sand and about 35-55% silt.
Clay, which is the finest of the three, is usually about 20-25% throughout the whole area called Langhe. Given its origin, the pH of the soil is alkaline (usually over 8).

The temperate climate – with rainy autumns and springs, hot summers and wide temperature variation before harvest time – is a second key-factor for the unique characteristics that Nebbiolo grapes have in this area.

An example.
Temperatures in La Morra, from March 15 to September 30, 2005.

In short, terroir is a well-defined area where natural, physical and chemical conditions, together with geography, climate and microclimate contribute to wines that may be distinctively recognised as belonging to that area alone.