Participatory Action Research (PAR) involving local communities and geological heritage were examined in the framework of the ‘Litoral del Biobío’ Mining Geopark project (Chile). A broad spectrum of the population was involved in testing the suitability of PAR methods to determine the sociological perception of geology, geo-tourism and geoconservation, and thus to contribute to define future local development initiatives. Specifically, 56 workshops were realized on basic geological concepts, field experiences in geosites, Strengths, Weaknesses, Opportunities and Threats (SWOT) analysis and identification of specific strategic plans. The study involved 637 participants, including local administrators, private companies, chambers of commerce and tourism, social entities, the general public and Lafkenche indigenous communities. Participants considered important the workshops and their learning about basic geological concepts. The main result of these workshops was the collection of information for the design of strategic plans for each of the communes and the empowerment of the local community. This was ratified by letters of commitment from associations and participants to the Geopark initiative. This research enabled the communities to identify four strategic areas: education; tourism; heritage; and public-private coordination, which will be considered in the elaboration of specific development plans. This bottom-up strategy has allowed demonstration that geotourism has the potential to contribute to the sustainable development of the territory, and can benefit areas with very different socio-economic realities: the indigenous peoples of the south, which are rural (sustained by agriculture and fishing) and those of the north, which lives mainly in highly populated cities with high unemployment, where industrial reconversion did not allow all of them to overcome the crisis after the closure of the mining industry.