An Islamic state under the leadership of a caliph

the Burj Khalifa, a skyscraper in Dubai that is the world's tallest building

Caliphate; the Islamic empire formed after the death of the Prophet [[穆罕默德|穆罕默德|mu4 han3 mo4 de2]] in 632.

the Rightly Guided Caliphs, referring to the first four successors of Muhammad from 632 to 661 AD