Excavations recently carried out in Lattes/Lattara (Hérault) had revealed a new window onto the foundation levels of that lagoonal protohistoric trading post, sparsely accessible due to the thickness of the stratigraphic sequence. These new data invite us to take stock of our knowledge about the nature of this first occupation and the role played by the Etruscans. The scale of the urbanistic program conducted by the latter at the beginning of the 5th c. BC is confirmed, as well as the brutal destruction that affects the site around 480/470 BC. The morphology of the block suggests the evidence of multi-room houses and a rigorous orthonormal plan. However, a new previous sequence was highlighted here, and corresponds to the strictly speaking installation phase. A regular division of the land precedes the building of a wattle-and-daub apsidal house which plan and metrology find convincing parallels in Padanian Etruria. This succession between a land division, a temporary settlement and an urban program testify of a real planned undertaking, that must be linked to the renewed commercial dynamic of the City-States of Southern Etruria at the end of the 6th-beginning of the 5th c. BC.