Like other medieval societies, Islamic culture centered around religion (Islam). In a culture based on religion, it is not uncanny to find that Islamic culture is predominantly non-secular. Most Islamic architectural achievements are in the form of mosques, which are Islamic churches. Many religious monuments are also among the best work of Islamic civilization.
One of the earliest Islamic monuments is the Dome of the Rock in Jerusalem. This monument has quite a significant religious history because it shares a geographical location between the Islamic world and the Jewish world. Muslims believe this is where the prophet Muhammad ascended to heaven, while Jews believe this is where Jesus died. It was completed in 692.
Considering the large extent of the Islamic Empire into North Africa, Spain, the Middle East, and India, we can see that much of Islamic culture was spread vastly throughout the "known world." In each of these areas we can see examples today of the Islamic architectural influence bestowed upon Islamic territory.
For example, in the 9th century a famous mosque was constructed in Cairo, Egypt under the Egyptian governor, Ibn Tulun.
Under the Delhi Sultanate (a dynasty of Muslim sultans or kings) in India beginning in 1192, Indian architecture began to express that India was under Islamic rule. This can be seen primarily by the type of construction that began to be widely used in India along with materials such as stone.
In Turkey a mosque was created out of the Byzantine church Hagia Sophia.
Shah Jahan built the Taj Mahal (1632–1650), in Agra, India originally as a tomb for his wife. In its extravagance and magnificence, many believe the Taj Mahal to be the most beautiful building in the world. The same people would agree that this structure is among the most grand contributions in architectural history.