Atar is purifying fire, the spirit of life, the hearth-fire, and the fire god. A Zoroastrian temple is a fire temple, where the eternal fire burns in its sanctuary. The building itself can be nondescript, and is without a standard plan.
The central temple of the Ateshgah at Surakhani, Baku, Azerbaijan, is a small, open structure with a chimney on each corner. A circular platform nearby features an eternal flame. The building as a whole is like a stone castle. The site originally featured “seven holes with burning flame” fueled by naptha deposits. The place was mainly a Hindu and Sikh shrine, and is a museum today.