 In particular, numerous references to Mount Sinai exist in the Quran, where it is called "Ṭūr Sīnāʾ", "Ṭūr Sīnīn", and "aṭ-Ṭūr" and "al-Jabal" (both meaning "the Mount").As for the adjacent "Wād Ṭuwā" (Valley of Tuwa), it is considered as being "muqaddas" (sacred), and a part of it is called "Al-Buqʿah Al-Mubārakah" ("The Blessed Place").The Eyüp district in the Turkish city of Istanbul is considered fourth holiest site by some sources.