As this area is the homeland of the Arabic language, it is common to expect the language spoken there to be closer to Classical Arabic. This is not the case. Although these dialect may have retained archaic features such as the conservation of nunation for indeterminate nouns, they are as divergent from Classical Arabic as other dialects may be (or sometimes even more divergent).
Yemeni Arabic, displays a past conjugation with ultra-archaic -k suffix, as in southern Semitic languages. It has to be noted that the particular dialect of Aden has /ɡʲ/ > [ɡ] as in Cairo.
Hejazi Arabic, spoken in Saudi Arabia along the coast of the Red Sea, especially in the cities of Makka and Jiddah. It is very closely related to the dialects spoken in Egypt and Sudan to suggest that these latter African areas could have been Arabicized with populations crossing the isthmus of Suez.
Najdi Arabic, spoken in the center of the peninsula in Saudi Arabia. It is characterized by a shift of /q/ to [dz] and /k/ to [ts].