Lava farms were areas worked by the Ta-Matoran in Ta-Wahi. In contrast to the once refined crafting procedures of Ta-Metru, lava farming was necessary given the large number of Rahi serving Makuta who made the manufacture and transport of items more difficult. Ta-Matoran began harvesting lava from the Mangai Volcano and cooling it, then using tools to shape it into items that might be needed (these were rough carvings, nowhere near the level of what Po-Matoran could do). These would then be shipped via underground tunnel to other villages. A number of lava farms were located in the Tren Krom Break.
Lava farming involved gathering and channelling lava so it could be cooled inside molds and used to make items. It was necessary because much less molten protodermis was available for this purpose on the island of Mata Nui.