Archaeologists in Pompeii have unearthed an ancient building site that sheds light on construction techniques used by the Romans to make iconic structures such as the Colosseum and the Pantheon, Italy’s culture ministry said on Monday.

The site was probably active until the volcanic Mount Vesuvius erupted in 79 AD, destroying Pompeii in southern Italy, the ministry said in a statement. The archaeologists found working tools, stacked roof tiles, tuff bricks, and heaps of lime and stones used to create walls.