Al-Masjid al-Ḥarām is the largest mosque in the world. Located in the city of Makkah, it surrounds the Kaaba, the place which Muslims worldwide turn towards while performing daily prayers and is Islam's holiest place. The mosque is also known as the Grand Mosque. It can accommodate up to four million Muslim worshipers during the Hajj period, one of the largest annual gatherings of people in the world. (source)
Saudi Arabia is the largest state in Western Asia by land area, constituting the bulk of the Arabian Peninsula. Saudi Arabia has an area of approximately 2,149,690 km2, and it has an estimated population of 27 million. It’s capital and largest city is Riyadh. Saudi Arabia has the world's second largest oil reserves and is the world's second largest oil exporter. (source)
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