This article lists some but by no means all of the oldest known minaret towers in the world.
The oldest minaret still surviving is that of the Great Mosque of Kairouan in Tunisia.
[1][2] It was constructed in 836 AD[3] and is considered as the prototype for all the square shaped minarets built in the Western Muslim World.
[3] Most ancient, surviving minarets were constructed adjacent to a mosque, for the Muslim call to prayer (Adhan) five times each day by a muezzin (crier).
[4] A few minarets were built as watchtowers, landmarks or symbols of victory or glory of a Muslim Khanate or empire.