The study of the climate in the last 2700 years reflected in the palaeo record is obscured by the strong influence of human destruction of forest cover during this period. In this study 2 sites in the Queixa Sierra (northwestern Iberian Peninsula, Europe), Castelo Cerveira (1380 m) and As Aguilladas (1580 m), provide insights into high montane forest dynamics in this area since 2700 years BP. The palynological record shows regional development of vegetation associated with forest clearance. Around 2700 BP a montane Quercus–Betula forest was destroyed, followed by an abrupt increase in grass and heather vegetation. Human impacts reached their maximum in the last 1000 years. Abundant microcharcoal particles, along with an increase in Cerealia pollen, indicate frequent fires and generally intense human impacts on the environment. Despite this deforestation, some temporary phases of Betula vegetation occur before the total disappearance of the natural forest and its replacement by plantations of (regional) pine forest.