Making Medieval Charcoal

At Coolnaleen Lower we found several charcoal-production kilns. Charcoal was an important fuel for metalworking in the past because it can reach the high temperatures (1000°C) needed to smelt both bronze and iron. Charcoal is made by burning wood in an oxygen-controlled environment.

In the past, charcoal was produced in special kilns. Pit kilns were the simplest kind. Wood was stacked in the pit, covered with vegetation and earth to prevent full combustion, and burned over a number of days to make charcoal.