The discovery of lignite in Andorra Historical milestone · Andorra, Andorra-Sierra de Arcos, Teruel Image of Andorra, not of the place itself. The discovery of coal in 1914 completely changed the local economy. The Barrabasa, María and Previsión Rectificada workings operated until the middle of the twentieth century and gave rise to the comarca's mining vocation. 1914 Photo: Zarateman (CC0) What to see and do in Andorra