The tatara (鑪) is the traditional Japanese furnace used for smelting iron and steel. The word later also came to mean the entire building housing the furnace.
The steel, or tamahagane (玉鋼), used in the forging of Japanese swords, nihontō (日本刀), commonly known as katana (刀?)) by contemporary Japanese forge masters like Kihara Akira and Gassan Sadatoshi is still smelted in a tatara. One of the few remaining tatara is the Nittoho tatara in Shimane Prefecture, Japan.