During the campaign which took place in July-August 2010 work continued in area IV which had already been investigated between 2005 and 2009. Trial trenches were also dug in the locality of Olmo di Costolino. This year the excavation at Spinellina aimed to clarify the dynamics of the stratigraphic sequence, that had already been uncovered, and the relationships between the layers.

The removal of the deep layers belonging to the dense band of materials denominated US 413, datable to the mid 7th century B.C., was completed. In particular, a dense sequence constituted by a succession of horizontal levels of detritus, pottery and abundant charcoal, intentionally dumped to fill a cut, or foundation trench was excavated. The latter, denominated US 530, had a sub-rectangular section and flat bottom. On average it was one metre wide and at the best preserved point was about 0.25 m deep. The interpretation of US530 is uncertain. On the basis of the data from 2010 it seems likely that these layers formed the make-up, also providing drainage, for a large structure (ascertained length about 6.50 m) which has been completely obliterated by ploughing.

The robber trench US539 is also datable to the early-mid 7th century B.C. Excavation of the fill, containing abundant pottery, was completed. This trench was situated at the centre between various structures denominated US413-530 and 409-555 and partially cut them. It was also seen that the fill of US539 had subsequently been cut by another ditch, filled with alternating dumps of grey earth with abundant charcoal and concentrations of medium to large sized cobbles (US 592 and US594). The latter is probably datable to the end of the 7th-first half of the 6th century B.C.

The narrow curving cut US571 can be interpreted as a robber trench filled with rubble from disused structures. The fill contained large fragments of baked clay and cobbles (US570, 583). From a stratigraphic point of view it seemed to coincide with the first phase of the cycle of activities removing and accumulating materials, which concluded with the creation of the cobbled surfaces US 375-409, investigated in 2005-2009.

In the eastern part of the excavation area work continued on the negative stratigraphy and the post holes associated with timber structures, some of which later than the 7th century structures. One of these structures was constituted by rows of small post holes (US510) which formed a corner, or more probably a curve, to the west. Another post hole (US581-582 was a continuation of this structure. Other cavities relating to timber structures were found further to the south (US 573, 575).

In the locality of Olmo di Costolino, situated north-east of the main concentrations of finds relating to the proto-historic settlement of Trebbio, a number of trenches were dug with the aid of a mechanical digger with the aim of defining the extension of the ancient settlement. The presence of the remains of rural structures of Roman date was ascertained (drainage channels, well, cobble-built walls), some of which overlying alluvial deposits relating to a probable pre/proto-historic expanse of water. This would seem to confirm the hypothesis that this area, although presenting traces of occupation in the same period as the occupation of Trebbio, was situated outside of the settlement and partially formed its north-eastern border.