Charcoal was the main fuel in the old days， which was used in cooking， heating， etc. Datun mountain region has rich resources such as acacia trees， and was an excellent place for the development of the charcoal industry. It was also the means of living when the ancestors first came to this place. For example， Wu's charcoal kiln in Zhongzheng Mountain of Beitou has a history of more than 160 years.Along Zhongzhengshan Hiking Trail (south of Datun Mountains)， due to fuel requirement， the charcoal industry flourished after Taiwan retrocession， until the ‘70s. However， with the rise of the oil industry， the charcoal industry went into decline and almost disappeared from Beitou District altogether. Today， even though the charcoal industry is no longer part of the economic activity， it has been appropriately transformed into a local cultural asset. For example， within "Erqi Farm" of Beitou Farmers' Association， there is a restored charcoal kiln which has stopped operation for 30 years. The top of the kiln is like an arched tortoise shell， and is covered with soil. A double-pitched thatched roof was constructed on top and a mono-pitched thatched roof， called "Gou-Zui-Liao-Zai" (dog mouth house)， was constructed above the combustion chamber to keep away the wind and rain. The owner of the charcoal kiln at Shibafen's farm demonstrates charcoal burning during the tour， and introduces tourists to this ancient industry.