Iron Age combustion structures on the eastern Iberian Peninsula have traditionally been analysed through the study of their morphological aspects and their association with archaeological finds. Approaches including microarchaeology and a combination of different disciplines are still rare for this area and period, despite the fact that they will be able to provide more information on the construction techniques, fuels and uses of fire facilities. The authors are currently undertaking the project entitled “Transdisciplinary and Experimental Study of Combustion Structures in the Western Mediterranean during Protohistory (first millennium BC)” (TRANSCOMB) aimed at implementing an interdisciplinary methodology for the study of protohistoric hearths and ovens. This paper presents the results of the analyses (anthracological studies, phytoliths and calcitic microfossils, micromorphology and FTIR) conducted on a selection of combustion structures. Micromorphological and FTIR analyses give us detailed information on the construction technique and materials used. Macrobotanical and microfossil records indicate fuel sources. The different analyses also provide information on the temperatures obtained in the studied combustion structures. The coordination between specialists and the comparison of results obtained from the different techniques have provided a complementary view of the aspects studied. These need to be extended by further research, including experimental work, within the framework of our project.