Muscat is the capital and largest city of Oman. It is the seat of the Governorate of Muscat. According to the National Centre for Statistics and Information (NCSI), the total population of Muscat Governorate reached 1.4 million as of September 2018. Oman shares a border with Yemen.

Sanaʽa is the largest city in Yemen and the capital of the country, although the seat of the internationally recognised government moved to Aden in the aftermath of the September 21 Revolution. Aden was declared as the temporary capital by President Abdrabbuh Mansur Hadi in March 2015.

Aden is a port city and the temporary capital of Yemen, located by the eastern approach to the Red Sea. Its population is approximately 800,000 people. Aden's natural harbour lies in the crater of a dormant volcano, which now forms a peninsula joined to the mainland by a low isthmus.

Al-Hudaydah also transliterated as 'Hodeda', or 'Hodeidah', is the fourth-largest city in Yemen and its principal port on the Red Sea. As of 2004, its population was 402,560.

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