1 INTRODUCTION This essay uncovers the variability and heterogeneity of the range of constructive types of corbelling domes across the Iberian Peninsula (Fig.1, 2). Two are the main architectural features that stand out in this study: the dry bonding technique without any mortar (both in stone and adobe masonry) and its direct relationship with the roof vaulting by corbelling. For this reason this research is focused on the dry stone bonding solutions and its transition into specific corbelling dome systems, implemented without any trace of mortar or holding up device. The corbelling technique is possible thanks to the courses’ progressive approximation and it has its source into the spontaneous covering of circular or polygonal spaces. According to archaeology the first examples of these constructions are the huts of some Middle East settlements like Arpasiyya y Tell Alaf (V Century A.C.). Whereas in West Atlantic and Mediterranean Europe corbelling system has been traditionally linked to megalith cultural phenomenon as it may be found in these big collective graves. At the same time in some Mediterranean islands the megalith building technique is expressed by monumental Bronze Age corbelling constructions. In this case, in Mallorca, Menorca o Sardinia Islands is possible to find examples of this, respectively in remains of talayots in Spain and nuraghe in Italy. The Iberian Peninsula witnesses a geographical synchrony between the areas of expansion of megalith culture and regions with great examples covered by corbelling domes. All this suggests that the origin of these outstanding shepherds and peasants shelters dates back to several millennia ago. Therefore, it could be stated that the Iberian landscapes are dotted with these timeless constructions, as ancient as shepherds and agriculture activities. According with this, the study reflects two different and compatible techniques applied to constructions: the dry stone walling system and, at the same time, the corbelling dome system. The walls, built either by limestone (East of the Peninsula i.e. Cataluña, Baleares, Comunidad Valenciana and Castilla la Mancha) or granites and slates (Northwest of the Peninsula i.e. Portugal, Extremadura and Galicia), are erected bonding the stones without cement or mortar. In some cases we may find adobe corbelled domes, but just in the area of Castilla-León, called Tierra de Campos, where there is a long-standing tradition of earth constructions within the world of vernacular architecture (Fig.3). Corbelling domes and bridges in Spain and Portugal: a comparative study Fernando Vegas- López Manzanares, Camilla Mileto and Valentina Cristini Polytechnic University of Valencia, IRP – Instituto Restauración del Patrimonio, Valencia, Spain ABSTRACT: Corbelling is a traditional old system to build arches and domes that consists in overhanging gradually layers of stone or bricks, rising all the way to the cap. In Spain and Portugal small primitive bridges and a great variety of corbelling domed huts mainly in vernacular architecture related to peasants’ and shepherds’ lives. This variety reflects not only in the dimension, shape and use of the huts, but also in the material and constructive details. These corbelling domed huts have been classified under their free-standing or grouped condition, layout, cross section related to structural functioning and type of dome, as well as their building material, building process, possible roofing, type of lintel, possible rendering. Although apparently fragile and unstable, this ancient type of arches and domes has proofed its suitability for different uses since centuries and its capability to survive without almost any maintenance.