 So thank you very much. So now I'm going to talk to you about a small site and a small excavation that we carried out in Northern Britain in Northern Western France. It's a small site, but it's a good example of public archaeology and coastal erosion in France. So the excavation that we carried out in 2015 and 2016 on the rocky islet of Roxantecléton is rocky islet here. It illustrates really well the difficulties of intervention both logistical and administrative. We present it here as a rather emblematic case study. How to save a prehistoric and prehistoric dwelling in the French coast at the beginning of the 21st century. So coastal erosion and anthropogenic pressure on the coastal strip combined their effects to permanently damage the tenuous remains left by prehistoric human groups. In the absence of the stroyer prayer link that has allowed the development let archaeology in France since the 1990s the preservation of this diffuse heritage on the coast is often under the responsibility of amateur archaeologists. A specific monitoring program such as alert directed by Marie van der or simplified and coordinated is essential work. Digging prehistoric sites on the coast is therefore an act underpin by an important and original problems for recent prehistory habitat or storage structures fisheries and foreshores or graves or archaeological elements that feed them. Three excavations carried out in coastal sites will serve as examples of practical application to these problems. Discovered in 1985 by Daniel Rue a volunteer prospector then operated as part of the alert project in 2015 and 2016 under the responsibility of two of us Gregor Marchand and Pao Olmos the rock scented let on rock shelter in Santec in northern northern britainy benefit from this heritage and scientific practice. The rocky island of Roxantec let on is almost two kilometers from the mainland and access on foot is only possible a few days a year or you can do it by boat but in the later case boarding in the middle of the rocks is extremely dangerous as soon as there are waves and winds the difficulty of access means that the site has not suffered from significant anthropogenic pressure but that on the other hand it's very heavily pounded by oceanic storms there waves exploding on the rocks strip the site as we can see if you compare these pictures in 1995 on these pictures in 2015. It was then necessary to adapt the methods of excavation of a prehistoric site to gain an efficiency with permanently in mind the rhythms of closure and opening of the land bridge or the possibilities of mooring by boat for all that we did not sacrifice the systematic swimming with water only possibility to detect the finnish lithic elements at the end of this of our intervention the archaeological levels most written by the ocean have been totally excavated and recovered there are no longer any hollow sand layers and 40 to 50 centimeters layers of place to sand lowest protects the levels of middle panoditic really well preserved. The site is at an altitude of eight meters that is to say three meters above the highest heights the preserved archaeological levels are on a platform this platform bordered by large rocks the northern block is a partially collapsed rock shelter and the levels inside the shelter were almost totally wasted away by the waves. This block collected at the after the occupation of the middle paleolithic but the protected level were not since the water from the waves ran off underneath facing east is the main excavation area along the west block is three meters three meters wide in 11 meters long excavation in this sector were carried out over a surface of approximately 19 square meters. The first our first speech in 2015 and the excavation in 2016 revealed a very rare stratigraphy in the region for a thickness of one meter at the base three levels here three levels of middle paleolithic are sealed under the silty levels of the last plenic glacier this 40 centimeters thick level is archaeological untouched at the top of that loss was a much damaged a pylian layer of final paleolithic followed by the allothing occupations of the early late and second metholytic a fire pit on the early neolithic and an iron age drilling. These four successive anthropogenic layers were excavated and seeped over a thickness of only 20 centimeters without strict sedimentary distinctions. For dates by radio carbon come to specify of this attribution even if it's difficult to correlate structurally archaeological objects and that's in a allosan ladder level rather disturbs. Stone structures as you can see here made of pebbles of pebbles are visible at the top of the stratigraphy. These are very recent and are linked to the hunting of seabirds a large herd dated to the iron age lay underneath these structures within a level of very underrated loss sealed. The ceramic the pottery consists of 234 charts with a total of five pots which is very low. Most ceramics can be dated back to the early middle second iron age. There is an absence of ceramic elements dating from the Gallo-Roman period such as such Italian amphora and seems to mark the abandonment of the site before the Roman conquest. Seven macro tools or anthropogenic elements have been identified in this upper level. They are generally tools on granite pebbles, they are very little invested. Used occasionally they are mainly used for specific crushing or percussing actions. The Gallic level also contains a small layer of consumed seashells. The study focused on the data obtained from sediment samples 20 liters taken during the 2015 excavation. Five species of marine selfish have been identified including four gas for pots and one b-bulb. The total is 247 fragments. Limpets are the most consumed seashells. They are in majority as you can see in the graphics. Wherever the type of quantification is used. We can say that the population of Roxantec during the iron age gathered the shells in a specific environment. Namely moderately to heavily beaten rocky areas where limpets, monodonts and mussels are collected. The shoves of these species can be explained by the environment surrounding the site probably composed of a dense rocky area as is in the case today. Indeed it is very likely that the prehistoric coastal landscape resembled the present landscape. I heard a face of limpets, a few hammers and some pouch during the iron age. The rock shelter of Roxantec letton is a temporary habitat on an island already separated from the continent. The flames of the Mesolithic lie in the lower part of the 20 centimeters thick Olythian soil without intrusion of Gallic shorts. One of the best identified levels corresponding to the early Mesolithic with some specific nucleus, a point with two slotted H and a row base two scallion triangles and four narrow lamella with slotted H. The presence of charred hazelnut shells allowed to obtain an absolute dating of 7800 calibrated BC in the transition period prevorial boreal. The existence of a level of the second Mesolithic 6800 BC characterized by the presence of four symmetrical trapezes and a truncated blade is also confirmed without sedimentary transition between the Mesolithic and the Latinian occupation. During the Mesolithic with a sea level between 30 and 10 meters below the present one, the rock shelter of Roxantec letton was attached to the continent and dominated a landscape difficult to describe now with a coast several kilometers from the north. A pit hearth was docking the Mesolithic in these Mesolithic levels. It was dated on charcoal to the interval of 4,800 to 4,600 which corresponds to the regional Neolithic tape between Nefs and Gertman. There are no water material elements of this passage to the Neolithic so is Roxantec already an island? The links between human societies and the maritime domain I don't know but at this time this short passage is not only going to enlighten on this question. Lowest levels here about 40 centimeters thick covers the site and protects a sequence of the Middle Paleolithic period. The presence of musterian litic pieces in the highest level remains Artenius and we have to be assessed during the subsequent excavations but such artifacts are very abundant in the three lower stratigraphic units. A series of 274 litic pieces must be attributed to the Middle Paleolithic. This assembly is in fact mainly composed of debris and thermally exploded size sketches and cutine products. This small litic assemblage presents quite strong typo-typocrological characters such as pretty well marked use of the Levalois method. The Middle Paleolithic occupation of Roxantec-Leton is part of a typical musterian with scrapers dominating the retorted tools and Levalois technology like many such in the arborican massif. The main scientific interest of the riskier excavation conducted on Roxantec-Leton was to document a very rare stratigraphy in western France. It extends from Middle Paleolithic to the Iron Age and even to the present if we take into account the recent hunting post. The elements collected are of local interest for the Iron Age and the early Neolithic of regional interest for the Mesolithic and the Middle Paleolithic. We try to combine the meticulous methods of praesoric excavation with an intervention in a difficult context with a schedule fluctuating according to tides and climatic hazards. At the present time and to finish, menace to the littoral sites are clearly not sufficiently taken into account by the French authorities and this whole heritage is still exposed to ongoing deterioration. Threats to much praesoric coastal sites are still poorly assessed by archaeological heritage managers. Reports of discoveries by non-professional archaeologists have been the first stage of alert for decades and, while it's still necessary, they can hardly be considered a sufficient evidence of these sites. We must no hope for an improvement in the management of these sites and anticipate their inexorable destruction. This will inevitably require additional financial resources for tidal intervention, but also convert some regulatory measures. For a site strutting the foreshore and the coast, authorization must generally be successively obtained from the regional archaeological service, the drasm, the conservatory littoral, and the locality in question. And curiously, the rate of the ocean doesn't seem to have the same calendar. Thank you very much.