It consists of searching in the field for trails or remains that lead, confirm or deny the evidence of a possible site.

This way, we base our research on two different technical methods:

• Non-intrusive survey: It consists of obtaining data that could have remained on the surface and which can be directly or indirectly related with the remains.
  It is important to highlight the study of the vegetation, according to its condition, growth stage and invasive typology, as well as the state of the soil on the basis of the substratum modification, thereby revealing a lack of continuity in the stratification in a concrete area, seen from a horizontal point of view.
• Intrusive Survey: Here it is necessary to modify the geological substratum to obtain data. This can be either punctual, through random or specific drilling or through the use of heavy machinery, depending on the site conditions.