What is the title given to ruler of Kingdom Saudi Arabia?

The title given to the ruler of Kingdom Saudi Arabia is 'Custodian of the Two Holy Mosques'. King Abdulaziz Al Saud took this title in 1926 when the Kingdom of Hejaz and Nejd was unified. The term 'Custodian of the Two Holy Mosques' refers to the responsibility of ruling over and safeguarding the two holiest sites in Islam - the Grand Mosque in Mecca and the Prophet's Mosque in Medina. This title is held by the monarch of Saudi Arabia and signifies the monarch's role as a protector of Islam's holiest sites and the Muslim community.