Hello,
Sasanian architecture refers to the Persian architectural style that reached a peak in its development during the Sasanian era.In fact part of Sasanian architecture was adopted by Muslims and became part of Islamic architecture.
Here,the Sassanid means a member of a dynasty of Persian kings of the third to seventh centuries.

We can find many examples of such architecture,some of them are :

• Baghdad
  

• The Great Mosque of Samarra

Hope it helps
Thank You !!