Vanessa Forte

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The content is published under a Creative Commons Attribution Non-Commercial 4.0 License.The Experimental Reconstruction of an Early NeolithicUnderground Oven of Portonovo (Italy)exarc.net/issue-2020-1/ea/exp-rec-neolithic-oven-portonovoPersistent Identifierhttps://exarc.net/ark:/88735/10478C. Conati Barbaro (IT),V. Forte (UK) andA. Rossi (IT)Issue 2020/1This contribution presents the experimental reconstruction of an underground ovenreplicated according to the archaeological evidence unearthed from the Early Neolithicsite of Portonovo-Fosso Fontanaccia (Ancona-Italy). A domed structure, measuring190x180 cm diameter at the base and 50 cm in height, was dug in 15 hours, in asediment compatible with the geological formation that features the archaeological site.The experimental protocol presented in this article aims to reconstruct techniques,timing and tools needed to dig the peculiar underground structures of Portonovo usedby Neolithic groups and understand key topics regarding the entire technical processsuch as energy investment for the community, seasonality and lifespan.The Archaeological Context The Early Neolithic site of Portonovo - Fosso Fontanaccia is located in the Marche region,along the Adriatic side of central Italy (See Figure 1) and is characterised by the exclusivepresence of underground ovens and by the absence of dwellings (Conati Barbaro, et al.,2013). The site belongs to the “Middle Adriatic Impressa culture” which developed during1/8the 6th millennium BC along the Adriatic coast of central Italy. Research carried outduring the last years unearthed 23 structures of fired earth in an area of 600m . Theovens have a circular base, from 1.80 to 2 m in diameter, a height of about 0.50 m, asingle central opening faced on a large pit. According to the archaeological investigation,each structure is characterised by a recurring lining, variable in thickness, probably dueto the repeated exposure of the sediment to the fire; moreover, the surface of the ovens’floors suggests a sort of intentional treatment likely by smoothing the superficialsediment at a wet state. This preliminary reconstruction is based on a first analysis oftechnical features of the archaeological remains and, in particular, of seven of the ovensthat were found completely intact (Conati Barbaro, et al., 2019) (See Figure 2). Archaeological material found inside the structures appears scantly whilst the most ofthe pottery, lithic industry, and faunal remains were unearthed from the large pitslocated in front of the ovens. Even a great amount of charred barley caryopses wasfound inside three of these structures (Conati Barbaro et al., 2019).According to the radiometric dating the site was occupied from 5900 to 5200 BC, aperiod during which the ovens were not all in use at the same time. Their spatialdistribution does not reflect a chronological order, although the location of each ovenwas probably well known when a new structure was to be built. Furthermore, some ofthe ovens were used for funerary purposes, as attested by the burials of three adultindividuals dating back to the last centuries of the 6th millennium BC (Conati Barbaro, etal., 2013).  The investigation regarding the function of this archaeological context availed ofarchaeometric analyses applied to the archaeological structures in order to address thebuilding process and the activities actually performed around of the undergroundstructures. The results of the PXRD analysis applied to the hardened sediment sampledfrom specific parts of four different ovens (floors, walls, vaults) suggest that temperaturereached by the structures did not exceed 500°C (Conati Barbaro, et al., 2013). Accordingto this data and to the great amount of charred barley caryopses found inside three ofthe ovens, it was hypothesised that these structures were used for activities of foodprocessing including roasting or drying cereals for their storage or consumption. In orderto confirm this reconstruction and contribute to the understanding of the function of thesite, an experimental replica of the underground ovens of Portonovo was built reachingthe actual size of the archaeological items. Very few reconstruction experiments of thesetypes of ovens have been attempted so far (Eiland, Luning & Williams, 2003; Lüning,2004) and since the main purpose of those experiments was to investigate the functionof the structure and its performance, the building procedure was not fully explained.Moreover, most of the building experiments performed so far have been focused ondomed ovens or earth ovens (e.g.: Đuričić, 2014; Costa, Cavulli & Pedrotti, 2017;Pfaffinger and Pleyer, 1990; Prévost-Dermarkar, 2003; Werner, 1991). This contributionwill present a detailed methodology to build an underground oven inspired by the shapeand size of the Neolithic structures unearthed at Portonovo.22/8The experimental replicaThe experimental underground oven was replicated according to shape, measurements,and technical features of the Neolithic structures found at Portonovo-Fosso Fontanaccia.The replica was carried out in three main steps including: (1) the preliminary set up of theexperiment, (2) the digging of the structure and (3) the final heating for consolidation.During the first step, we identified a sediment highly compatible with the ancientgeological formation chosen by the Neolithic groups that dig the prehistoricunderground structures (See Figure 3); we proceeded with the removal of the vegetationfollowed by the preparation of the excavation wall and a pit in front of it about 1.80 x1.50 m wide. The set up step included also the collection of tools necessary to dig theoven; the selection was made according to wood species attested in this area during theNeolithic period, and animal bones. The selection of these kinds of tools was madeaccording to the raw materials commonly used in well preserved Neolithicarchaeological sites, such as La Draga, in Spain, (López et al., 2012, Palomo et al., 2011)and La Marmotta in Italy (Fugazzola Delpino, D'eugenio & Pessina, 1993). These findingstestify the large production and use of wood and bone tools by Neolithic communities.Conversely, the selection of wood tools with long handles currently lacks of directarchaeological evidence in particular in the archaeological site of Portonovo;nevertheless, the possibility to reach easily the deepest areas of the underground oven,working from the outside, led us to test their efficacy. We collected tools made of oak (Quercus robur L.) exhibiting a thin utilized edge and along handle (1.67m) along with other two implements, of different dimensions, made ofacacia (Robinia pseudoacacia Mill.) characterized by a curved working edge and a longhandle (65cm); we also tested several wood wedges and a wood mallet (Ligustrum vulgareL., Castanea sativa L., Populus nigra L.). Furthermore, a tool made of a bovid bone (Bostaurus L.) was utilized as well, featuring a sharp edge and a wooden haft, which was linedwith leather to favour its gripping (See Table 1; See Figure 7).tool shape andsizematerial use activity technicalstepefficacystick thin edgeand a longhandle (1,67 m)wood(Quercusrobur L.)dig (directpercussion)during thewholeprocesshighstick shortcurvededge andlonghandle (65cm)wood(RobiniapseudoacaciaMill.)dig (directpercussion)during theinitialprocesslow3/8stick curvededge andlonghandle (80cm)wood(RobiniapseudoacaciaMill.)pull out thesediment resultingfrom diggingduring thewholeprocesshighwedge sharp edge(30 cm)wood(Ligustrumvulgare L.)dig (directpercussion)during theinitialprocesshighwedge sharp edge(30 cm)wood(Castaneasativa L.)dig (directpercussion)during theinitialprocessmediummallet hammershaped (40cm)wood(Populusnigra L.)direct percussionon malletjust at thebiginningof digging highhighscraper sharp edgeand awoodenhaftbone (Bostaurus L.)removeirregularities ofthe internalsurface followingthe diggingprocessafter thedig of theovenmediumTable 1. Tools selected and used during the experiment. Each tool is described inshape, size, task and efficacy of its use in each specific step.During the second step of the experiment that coincides with the digging of thestructure, we proceeded engraving the limits of the entrance along the main wall (SeeFigure 4). We started this phase using a wooden mallet (See Table 1). Once reaching a 10cm ca. deep entrance we started to dig the structure, shaping the oven within thesediment until we created a dome measuring 190x180 cm in diameter at the base and 50cm in height. A total amount of the sediment corresponding to 0.786 m  was extractedutilizing wood wedges and a wood mallet throughout direct and indirect percussion (SeeTable 2; See Figures 4 and 6). The sediment detached through the percussion gesturewas pulled out of the structure through a wooden tool with a flat functional edge and along handle in order to reach the deeper areas of the oven and clean the floor fromsediment residues (See Figure 6c). This gesture was performed at each step in order toavoid an accumulation of the sediment inside the structure that usually made difficultthe working. During this phase the experimenter, a young man working on his own,performed the entire technical sequence in a supine position (See Figure 6 d); the use of34/8long tools made it easier for the experimenter to work from inside and reduce the risk incase of a collapse of the structure. The pit found as a recurrent structure developing infront of the ovens favour these operations.hours oven measuresdepth width frontal height central height rear height1° 40/42cm57 cm 36 cm − 28 cm2° 64 cm 81 cm 33 cm − 25 cm3° 80 cm 86 cm 29 cm 27 cm 20 cm4° 85 cm 96 cm − 32 cm −5° 97 cm 97 cm − 36 cm −6° 106 cm 113cm− − −15° 180 cm 190cm50 cm 50 cm 20 cmTable 2. Measurements and timing necessary to build a replica of the Neolithicoven of Portonovo.Once the dig ended, we used a bone tool with a sharp working edge in order toregularise the inner surface and the outer wall and remove the irregularities due to theshaping step (See Figure 7). Nevertheless, given the regular and smooth surface of thebases in the archaeological ovens, we decided to adopt two different surface treatmentsin order to investigate possible different refining techniques of the surfaces and testmore than one reaction of the sediment to fire contact. For this reason, half of thestructure was left unmodified, without any other treatment on the surface; the other halfwas instead smoothed through the application of water in order to spread the sedimenton this area of the floor. In the latter case a homogeneous coating was produced (SeeFigure 8). The final step of the experiment coincided with an intentional heating of the oven inorder to expose the sediment to high temperature and ensure a consolidation of theentire structure (See Figure 9 a). After the first firing the structure showed a light-yellowcolour and a solid consistence in particular along the areas refined with water (the floorclose to the entrance) (See Figures 9, b-c). After a sampling of the sediment in order to apply archaeometric analyses, we observedthat the first consolidation process was probably not enough to obtain a fired clay having5/8a thick layer compatible with the one observed during the dig of the archaeologicalstructures.Creating a fire within ovens like these which lack a vertical draft, is not an easy task, andthe fire struggled to start, however, the oven worked well once the gaseous componentsof the fire found their path throughout the dome (See Figure 9d). This confirmed that theoven can work efficiently with a vertical draft system allowing the smoke to get outthrough the entrance of the oven, and suggesting that a vertical hole along the dome isnot necessary in these kinds of structures to make them functional.ConclusionsThis contribution presented the technical sequence necessary to build an experimentalreplica compatible for shape, measurements, and functioning with the archaeologicalovens found in the Neolithic site of Portonovo-Fosso Fontanaccia (Italy). Theexperimentation provided new data regarding resources, digging techniques andphysical efforts that allowed us to address the function of such a peculiar archaeologicalsite and the Neolithic communities that lived in this area. According to the experimentalresults a dome underground oven measuring 190x180 cm in diameter at the base and50 cm in height can be dug in 15 hours of work by a single person as suggested by theperformance of the young man that carried out the experiment. An almost 2 m widestructure can be shaped using wood and bone tools to remove the sediment, shape thedome and refine the surface. According to the shape of the oven, its position and therecurrence of wide pits in front of the archaeological items, it is a possible hypothesisthat the predominant working position of the performer is supine, taking advantage bythe space in front of the oven, and this can be favoured by using tools with long handleto reduce the working time spent within the oven. Nevertheless, we cannot exclude thatpeople would never enter the structure for carrying out the construction. Tools used were enough resistant to be hypothetically reused for digging otherstructures and some of them worked with major efficacy compared to others (See Table1). Moreover, a high compatibility was ascertained between the traces left by the woodentools with long handles along the internal surface of the experimental oven and thetraces visible along the internal dome of the archaeological structures (See Figure 10). The results show that it is possible to excavate an underground structure starting from aproper exposed sediment section, and then enlarge it in width and in height. We also observed that the first attempt to consolidate the structure by firing was notsufficient to reach the thickness of the inner coating of fired clay that features thearchaeological ovens. Probably this result follows several heating or phases of use duringtime. The traces left after the firing on the inner walls of the oven confirmed a possiblefinishing phase of the internal walls throughout the smoothing of the more superficialsediment by the addition of water. Another important aspect was considered at the end of the experimental protocol.6/8Indeed, the possibility to carry out the building of such a peculiar oven allowed whoworked on this research to take part directly to an experiential activity developing adeeper perception of what actually required an activity like this in terms of physicalefforts and timing necessary to build an underground structure. Although at a very firstmoment the experiment was scheduled in order to understand the technical sequenceof production of the Neolithic ovens of Portonovo, at the end of the experiment newquestions and preliminary hypotheses arose. Indeed, it emerged how this activity doesnot necessarily require a collaboration of many people and building a new structurecould not be considered a particularly heavy task. This does not exclude any form ofcollaboration in the oven building but at the same time, on the basis of the experimentaland experiential activity, we can affirm that the building on an underground oven waspossibly accomplished by a single person in more than one step (15 hours in totalaccording to the experiment). Moreover, the strength and resilience of the sedimentcould suggest that each oven was enough resistant to be used also multiple times beforeits dismiss. Future research will be focused on the use of the experimental oven in orderto address the activities actually performed in such a peculiar archaeological context.About Authors:Cecilia Conati Barbaro (IT)Department of Classics, Sapienza Università di RomaVanessa Forte (UK)McDonald Institute for Archaeological Research, Cambridge UniversityAlberto Rossi (IT)Officina TemporisBibliographyConati Barbaro, C., 2013. Cooking, working and burying in Ancient Neolithic: the ovens ofPortonovo (Marche, Italy), with contributions of P. Acquafredda, P. Catalano, A. Celant, S. diGiannantonio, R. Lelli, I. M. Muntoni, M. Pallara, G. Ruggero. Origini XXXIV: 31–82.Conati Barbaro, C., La Marca, C., Forte, V., Eramo, G., Muntoni, I. M. and Rossi, A., 2019.Firing the earth. The early Neolithic ovens of Portonovo (Marche, Italy) . In: D. Georgiou, ed.Architecture of fire. Oxford: Archaeopress, pp. 16-29Costa, A., Cavulli, F. and Pedrotti, A., 2017. Firing Pits at Lugo di Grezzana: anexperimental approach. In: R. Alonso, J. Baena and D. Canales, (ed). 2017. The Significanceof Experimentation for the Interpretation of Archaeological Processes: Methods, Problems andProjects. Madrid: Universidad Autónoma de Madrid, pp. 255-259.Đuričić, A., 2014. The Construction and Usage of the Neolithic Oven: ExperimentalArchaeology. In: S. Vitezović and D. Antonović (ed) 2014. Archaeotechnology: studying7/8technology from prehistory to the Middle Ages. Beograd: Srpsko arheološko društvo, pp.257-276.Eiland, M. L., Luning, J. and Williams, Q., 2003. Technical analysis of earth ovens fromNieder Morlen. In: I. Prudencio M. I. Dias and J. C. Waerenborgh, (ed). 2003.Understanding people through their pottery. Trabalhos de Arqueologia, 42, pp. 71–81.Fugazzola Delpino, M. A., D'eugenio G. and Pessina A., 1993. "La Marmotta" scavi 1989.Un abitato perilacustre di età neolitica", Bullettino di Paletnologia italiana, 84, pp. 181-304.López, O., Palomo, A., Piqué, R. 2012. Woodworking technology and functionalexperimentation in the Neolithic site of La Draga (Banyoles, Spain). ExperimentelleArchäologie in Europa, 11, pp. 56-65.Luning, J., 2004. Zwei bandkeramische Grubenofen von der Aldenhovener Platte imRheinland. Mit Beitragen von Murray Eiland und Ludwig Reisch. In: B. Hansel, (ed). 2004.Parerga Praehistorica. Jubilaumsschrift zur Prahistorischen Archaologie. 15 Jahre UPA. Bonn.Universitatsforsch. Prahist. Arch. 100, pp. 11–68.Palomo, A., Gibaja, J. 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The experimental reconstruction of an Early Neolithic underground oven of Portonovo (Italy)

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The experimental reconstruction of an Early Neolithic underground oven of Portonovo (Italy)

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