An area in which a population of organisms can survive through a period of unfavourable conditions, such as an ice age or prolonged drought.

Often explains modern patterns of biodiversity — regions that served as refugia during the Ice Ages typically contain higher species richness than surrounding areas.

From the Latin refugium, meaning shelter or refuge — a place to retreat to when conditions elsewhere become uninhabitable.

The Iberian Peninsula, the Balkans, and Italy are considered the three major refugia from which much of European fauna recolonised the continent after the last glacial maximum.

The concept was first proposed by German botanist Adolf Engler in 1879, who noticed isolated mountain forests shared flora with distant coastal regions and hypothesised past land bridges.