Custodian of the Two Holy Mosques

The Custodian of the Two Holy Mosques (abbreviated as CTHM; Arabic: خَادِمُ ٱلْحَرَمَيْنِ ٱلشَّرِيفَيْنِ, romanized: Khādim al-Ḥaramayn aš-Šarīfayn, lit. 'Servant of the Two Noble Sanctuaries'), or Protector of the Two Holy Cities, is a royal style that has been used officially by the monarchs of Saudi Arabia since 1986. The title has historically been used by many Muslim rulers in the past, including the Ayyubids, the Mamluks, the Ottomans and the Sharifain rulers of Hejaz.

Source: Wikipedia — Custodian of the Two Holy Mosques (CC BY-SA 4.0)