Archaeological excavations carried out at Turó del Calvari (Tarragona, Spain) have revealed a protohistoric building interpreted as one of the earliest enclosures of power operating during the Early Iron Age in the northeast of the Iberian Peninsula. The structure is exceptional in several respects: the techniques of construction, the materials used, and the topographic situation. The building is perfectly integrated in the landscape and has an exquisite geometrical design, with measurement units based on the Iberian foot. The intended beauty in having used the golden ratio in its construction and an orientation that is both stellar and solar demonstrates the existence at that time of a complete series of mechanisms of representation and territorial control. This was based on the use of rituals and feasts as elements of political cohesion by an emergent elite within a process that reproduced a scaled-down Mediterranean cultural system in an indigenous space.