Zibad Castle is one of the four historical monuments of Zibad. It is located in
Gonabad and is believed to be the last shelter of the last Sasanian emperor
Yazdegerd III. It was registered in 2001 as an Iranian national heritage property, as it is related to the history of pre-Islamic
Iran. There is the royal castle nationally registered in 2002 under the name of Shahab Castle. Sources conflict as to the exact manner of the emperor's final moments. One suggests that after his defeat, he sought refuge at a mill near
Marv, the latter who killed Yazdegerd in order to obtain his jewelry.
The Cambridge History of Iran states that the miller was sent by
Mahoe Suri. According to the history of Belazari,
Yazdegerd III was defeated in a war in the city of Gonabad. According to the excavations of Zibad-Gonabad Fortress and according to oral narrations and the report of Blazeri and Habib Abdolhai, Dr Ajam and Abas Zmani (historical study magazine 1974), it seems that the narration related to the murder of Yazdgerd in
Merw Mill is more mythical than fact. What is closer to the truth is the narration of
Al-Baladhuri in
Kitab Futuh al-Buldan, that he was killed in Gonabad. The main text of Blazeri's book The Fate of Yazdgerd III: Then he went to Khorasan, then he went to Janabad (
Gonabad) he was welcomed and ruler of Merv send Nizak Trkhan to welcome him in Gonabad. but after weeks he asked the emperor to marry his daughter and the emperor refused and this caused a war and at the end Nizak defeats the king's army and destroys and captures remnants of the imperial forces. The battle occurred in Zibad
Gonabad.
Mahoe Suri was probably from the
House of Suren, one of the
seven Parthian clans of the Sasanian state. During the
Islamic invasion of Iran, Yazdegerd III went to refuge in
Marv; on his way to Merv he stayed in Gonabad Mahoe. The envoy warmly received them.
Mahoe Suri used opportunity to secretly plot with the
Hephthalite ruler Nizak against Yazdegerd. Regardless, the death of Yazdegerd marked the end of the Sasanian Empire, and made it less difficult for the Arabs to conquer the rest of Iran. All of
Khorasan was soon conquered by the Arabs, who would use it as a base to
attack Transoxiana. The death of Yazdegerd thus marked the end of the last pre-Islamic Iranian empire after more than 400 years of rule. An empire–which had a generation earlier briefly conquered
Egypt and
Asia Minor, even
reaching as a far as Constantinople, fell to a force of lightly equipped Arabs that were used to skirmishes and desert warfare. The heavy Sasanian cavalry was too sluggish and systematized to contain them; employed light-armed Arab or East Iranian mercenaries from Khorasan and Transoxiana would have been much more successful. == Sights and attractions ==