A further period of drought caused the level of the lake to drop by over 60 cm, in some points 12 to 13 m of the lake bed were exposed between the water’s edge and the bank. This revealed a stony stratum along the EN and NW banks. In some cases wooden structures appeared immediately and were visible among the stones, others were below 2.5-5.00 cm of sandy gravel. The stony feature, which in the northern area was perfectly preserved, was an ancient ground surface. As in 2005 the materials scattered over the surface were plotted and levels were taken. It was decided to investigate part of the northern area. A floor, US 4, was exposed and sampled for xylotomical, dendrochronology and radio-carbon dating, as was undertaken in area E. Thanks to a sample from a horizontal trunk of alder this structure provided an absolute C14 dating of 4840-4710 BC cal.1 σ. Further dating came from a collapsed vertical structure: 4800-4680 BC cal. 1 σ. Pottery fragments were rare and small. The materials collected were dominated by evidence of the lithic industry. A concentration of flint nodules was identified (US 48) which had been tested in order to gauge the quality of the raw material. Given the exceptional nature of the wooden structures and their state of preservation, a cast was made to be left on view in the archaeological park (put on show 7th August 2007). The absolute dating obtained from the posts and planks from the excavated structures and those identified along the eastern bank in 2005, led to the identification of two different settlement phases, within the space of a few metres, with an interval of 100 years (relating to the middle and late Neolithic): 4720-4600 BC cal 1 σ ; 3630-3380 BC cal.1 σ.

Investigations were undertaken on two fronts. 1) At the centre of the island in correspondence with the area excavated by Bertolone in 1953-59. Here part of a dump directly overlying the wooden Neolithic structures was removed. 2) In order to move an ENEL electricity cable crossing the excavation a trench was dug which itself revealed levels and layers of 16th-15th century and medieval date, some still intact, documenting the island’s more recent occupation history. It was seen that the museum’s façade rested on a wall 1.10 m wide which probably relates to the ancient church of S. Biagio. Other walls, probably Renaissance, were identified along and parallel with the west bank. Two stratigraphic sequences were exposed: 1) datable to the Bronze T/F and some time during the Neolithic period 2) the second dated to the late Neolithic period and produced the absolute dating of a post of 3660-3530 BC cal. 1σ. The line of the bank of the west coast which had emerged from the lake was plotted and levels were taken. The same type of stony feature as seen in 2005 and 2006 on the north and east banks was also seen here.

The reopening of part of the “Bertolone 1953-59” excavations (ex qq I-IV), formed the basis for the continuation of research into the various Neolithic as well as Enolithic and Bronze Age phases. In 1953 Bertolone had opened an excavation at the centre of the island with a trench on a north-south alignment, 1.80 m wide and 5.70 m long, to be used as a guide excavation. Thanks to his notes, sketches and photographs from 1953 and 1956 it was possible to expose the cut of the 1953 trench. In the north-western corner an area was identified which at the time had been used as a passage for the removal of excavated earth. The section of this unexcavated area (sez. N CD /4), was sampled for palaeo-botanical and radiometric analyses. Between September and October two sections were removed and taken to the Museo Preistorico dell’Isolino. These went on display on the 18th April 2009 together with an information panel which also shows the dating hitherto obtained.

The geo-referenced points that had been positioned across the island on various occasions were collated. Excavation of the area extended to the north of Bertolone’s area continued. Here in 2008 a disturbed sandy silt soil with the presence of recent, but not contemporary, intrusions was identified below circa 20 cm of humus. The underlying stratigraphic unit was uncovered comprising a silty-clay, slightly sandy with occasional gravel and abundant cobbles of varying sizes with a particular concentration in the eastern area. The disturbed stratigraphy was indicated by the presence of imbrices and bricks which, however, were not very recent. Given the proximity of trench A (2007 campaign) to the Museum (ex church of S. Biagio) and the medieval finds, these fragments may have been part of the church roof or repairs to the latter. Various interventions with dumps were documented by post-holes, some with stones to act as wedges for the posts, trenches and by the and from the underlying and successive contexts 202-341 and 203.The materials were physically heterogenous with various degrees of drift; this was probably dumped earth containing materials dating to the Late/Final Bronze Age associated with rare brick fragments whose presence may be due to movement by roots or animal burrowing. The final US excavated was a land reclamation layer. At the top of the layer there were some stones, their number increasing at the base. The stones presented various alignments. A first analysis suggests this material dates to the late/final Neolithic period. The excavation terminated in correspondence with large structured cobbles and US 417. Using a Multibeam device a geo-referenced bathymetry survey was made of the stony feature surrounding the bank of the Isolino to the east, north and west (the east and north areas were partially investigated in 2006) and continuing to the north-western extremity of the island with a ramification on a south-north alignment towards the Biandronno shoreline. In the areas investigated (east and north) Neolithic pottery and lithics were present on the surface of the stony feature. The readings with the echo-sounder were undertaken at 10 x 10 cm. In fact, the feature forms a monumental plateau extending into the lake at between 16 and 26 m from the present shoreline and terminating in a scarp. The height of the scarp’s summit is constant around the island at about 237.20 m a.s.l.

The CNR-IDPA of Milan took palinologiocal core samples (VIR3/3bis) from the site with the aim of reconstructing the environment and human impact in the Isolino area between the end of the 6th and the 5th millennium B.C. The samples were taken from trench D, situated on the west bank of the island where in 2007 a stratigraphic sequence was identified which included a late/final Neolithic layer and for which there is an absolute date (3660-3530 B.C.). In October, in occasion of a visit by the ICOMOS inspector the first results were presented on display panels. Area at the centre of Isola: In the extension to the north of Bertolone’s excavation (1953-59) the following layers were exposed a) US 201, disturbed in antiquity, as was noted in 2009, it contained late/final Bronze Age material as well as Eneolithic and Neolithic finds; b) the underlying cobbled surface US 442, dating to the Bronze Age, but as yet not precisely datable as it is unexcavated; c) the layer of reclamation US 200, that showed signs of earlier anthropological activity, it contained small pottery fragments and lithic elements attributable to the Neolithic/Eneolithic, on the basis of the latest radiometric analyses it seemed to have been formed during the Early Bronze Age: LTL5429A: 3587±45 BP-2130-2090BC; 2050-1860BC; 1850-1770. The late/final Neolithic occupation layer US 417 associated with a dwelling was identified. It was constituted by a collapse of large flat stones (US 428), already partially visible at the top of US 417, and others used as wedges; a central area with a beaten surface US 429 delimited by US 428, as well as post holes (US 427, 431,433, 435, 437,439). Lagozzian forms and elements were present (kidney-shaped weights, decorated plates, carenated bowls, transverse choppers associated with elements of the Breno type as well as elements that were clearly Eneolithic. This situation presented very close parallels with the materials from the late Neolithic levels at Monte Covolo. In this part of the island the Neolithic inhabitants established themselves in a natural depression (US 440) created in a layer of alluvial sand which delimited the surface of cobbles and pottery (US 441) below the above mentioned dwelling. A part of this cobble surface, which contained an abundance of pottery fragments, some large, has been left in situ for future viewing by visitors.

During the 2011 campaign a number of photogrammetrical techniques were devised in order to create a complete 3D reconstruction of every detail of the stratigraphy, thus perfecting thousandth the standard archaeological documentation usually in use. Area at the centre of the Island: the 2011 campaign continued in this zone with the excavation of the cobbled surface US 442 ascribable to the early Bronze Age (so far, for this period the available date is LTL5429A: 3587±45 BP). Continuing, Neolithic layers were investigated: US 441, 480 (in AE 6-9), part of structural elements (below the remains of the dwelling US 429, 428 with relative postholes investigated in 2010), the finds including pottery, lithic industry, grindstones, smoothing stones and hammer stones. Substantial traces of pigments were found both in these layers and in those above, in some cases found as loose powder, in others on cobbles, some of which were painted. Last year, late/final Neolithic occupation was attested by a dwelling (US 417, a collapse large flat stones and beaten surface at the centre of the dwelling overlying the remains of another residential structure). This year the excavation of US 441 and 480 revealed further structural elements US 481 and 448. The stratigraphic sequence investigated so far is of great importance for the understanding of the questions regarding the Chassey-Lagozza period, the late and final Neolithic periods and the transition to the Eneolithic period. Elements of the Lagozza type were present (such as transverse flakes and blade industries, kidney-shaped weights, decorated plates, carenated bowls, dishes) associated with elements of the Breno type together with clearly Eneolithic elements. Twelve erosion markers were placed along the north, east and part of the west bank (iron rods 12 cm thick, 2. 00 m high) in order to carry out precise monitoring of the lake-bed.

Centre of the island: The 2011 investigation of a dwelling terminated with the uncovering of a surface made up of stones (US 481), of US 448, and of layer US 477; the 2012 campaign completed the excavation of this Final Neolithic structure. It appears that the layers excavated this year also date to this period as forms and materials of Lagozzian type, such as transverse arrowheads and stone blades, kidney-shaped weights, spindle whorls, and Breno type elements continued to be present. As regards US 488, the mixed soil composition and the small quantity of fragmented sporadic finds it contained, suggest this was a layer of dumped material. The excavation exposed a stone and ceramic floor (US 483) below which was a layer of sands, silt, and clay, US 462. In some places it filled small holes that had naturally opened in the sands and the gullies formed by the erosion which in several points had dislocated or removed the surface (US 486). Three green stone axes were found in quite close proximity in US 462. One was very fragmented, only a small section of the cutting edge was intact, the smallest had a slightly damaged cutting edge. The largest axe was very well-preserved and had been placed inside a hole. Shoreline areas and south-eastern area: In 2009, given the need to define the total extension of the of this exceptional archaeological deposit in order to ensure its correct conservation and safeguarding, a general survey was made using a Multibeam. This examined the shoreline and the make-up constituted by different sized stones (which to the north overlay the early Neolithic timber structures) to the east and west. This year a systematic underwater survey was carried out. An examination was made of the medium and large boulders (situated at the base of the scarp, which bordered the make-up and the raised area with stones, a sort of “dam” continuing to the north/north-west towards the Biandronno shore). It was seen that along the eastern shore, starting from the mooring, towards the south, there was a substantial concentration of piles, including the remains of a palisade. Other pile structures were identified to the south-west in the shallow water, as well as along the eastern shore and to the north-west on land. The underwater research led to the discovery and investigation of the concentration of piles seen in 1863 by Antonio Stoppani and Desor e.De Mortillet in the south-east part of the island. An area of 90 m2 was surveyed and recorded and samples taken from the piles. Three other concentrations of prehistoric piles were discovered in the north-western and northern areas (an area investigated in 2006 and datable to the early Neolithic period: 4910-4580 B.C.). Core samples were taken both in the water and on land along two axes (N-S and E-W), traced so as to pass where there was a known stratigraphic sequence and, when possible, a known date.