Between 2010 and 2012, Ghent University and Utrecht University investigated the largest cistern in Thorikos and its immediate surroundings: Cistern No. 1. Whereas most cisterns in the Lavriotiki had been emptied during the 19th and 20th century activities of the French Mining Company or during more recent archaeological excavations , it seemed that Cistern No. 1, a rectangular structure, had remained intact. Moreover, the fact that its sides had not only been partially cut into the bedrock but also partially built in monumental ashlar masonry with huge boulders suggested that excavation on the outside would be able to provide material indicative of the chronology of its construction. The finds from these excavations have since been inventoried and studied, allowing for a comprehensive publication currently in preparation. The cistern had been built in the late 5th or early 4th century BC at the earliest, and seems to have gone out of use by the end of the 4th or early in the 3rd century BC. Its fill consisted of eroded material of the Late Archaic to Early Hellenistic periods that had been washed in over the years from higher up the slopes, but remarkably also a portion dating to the Late Roman and Early Byzantine periods (6th – 8th centuries AD). The metallurgical workshop (ergasterion) to which the cistern belonged was associated with Mine No. 2 and consisted of several rooms adjacent to the cistern, a crushing table, and a washery.