Blacksmiths used charcoal for firing their forges because it produced a hotter fire and burned more consistently than an ordinary wood fire. Most smiths made their own charcoal and the charcoal kiln outside the smithy serves as an introduction to that trade.
The kiln on the Ambagswerf is a replica of a charcoal kiln built in the eighteenth century. It takes many hours, even days, to reduce wood to charcoal and the charcoal-burner had to stay close by, even at night, to keep watch.