The Espaakho building has been registered among Iran’s national historical monuments and is considered to be unique in comparison to other historical monuments of Bojnourd. It dates back to Sassanid era and is made of stones and mortar. There is a balcony in the eastern corner of this building. Experts’ viewpoints in regard to application and function of this monument differ. However, it seems that this historical monument had been a Zoroastrian temple. This historical monument is situated a hundred kilometers west of the city of Bojnourd, next to the route linking this city to Golestan Province.