An hórreo is a granary built in wood or stone, raised from the ground by pillars (“esteos”, in Galician) ending in flat stones or “mueles” or “tornarratas”, to avoid the access of rodents. Ventilation is allowed by the grooves in its walls. In some areas, hórreos are known as hórreo, paneira, canastro (Galician), espigueiro (Portuguese), stabbur (Norwegian), härbre or more precisely stolphärbre orstolpbod (Swedish)
Hórreos are mainly found in Northwest Spain (though there are also in other Northern villages). There are two main types of hórreo, rectangular-shaped, the more extended, typical from Galicia and square-shaped from Asturias and eastern Galicia. The oldest Spanish document containing an image of an hórreo is the Cantigas de Santa María by Alfonso X “El Sabio” (song CLXXXVII) from XII A.C. In this depiction, three rectangular hórreos of gothic style are illustrated. The longest hórreo in Galicia is located in Carnota, A Coruña and is 35 m long.
Here are some photos I took of the longest horreo:
Other similar granary structures include Asturian paneras (basically, big hórreos with more than four pillars), cabaceiras (galician round basketwork hórreo),espigueiros or canastros in northern Portugal, (the most famous concentration is located in Soajo), trojes or trojs in Castile or silos, and Balkan hambars.
The origin of the horreo is the horreum from the Roman Empire, and is an old technology nearly disappear in the rest of the empire.
Härbren exist throughout Sweden, but the more hórreo-like härbren, raised from the ground by pillars, are only found in the central and northern part of the country. The church häbre (kyrkhärbret) in Älvdalen, Dalarna, built circa 1285, is one of the oldest surviving non-religious wooden buildings in Sweden.