Short answers, pulled from the story.
Sanaa is the capital and largest city of Yemen. It sits at an elevation of 2300 metres next to the Sarawat Mountains, making it the seventh highest capital city in the world, nestled between Jabal An-Nabi Shu'ayb to the west and Jabal Nuqum to the east.
Sanaa has a population of approximately 3,300,000 as of 2023, making it Yemen's largest city. As of 2020, the greater Sanaa urban area made up about 10 percent of Yemen's total population.
Sanaa remains the capital under the Yemeni constitution, but the seat of government moved to Aden after the Houthi takeover. Then-president Abdrabbuh Mansur Hadi declared Aden the temporary capital in March 2015. The Houthis seized control of Sanaa on the 21st of September 2014.
The Old City of Sanaa was declared a UNESCO World Heritage Site by the United Nations in 1986. It has been inhabited for more than 2,500 years and contains more than 100 mosques, 12 hammams, and 6,500 houses surrounded by ancient clay walls 9 to 14 metres high.
Sanaa could be the first national capital in the world to completely exhaust its water supply. Water extraction from the Tawilah aquifer exceeded the natural recharge rate by around 300 percent in 1995, with more recent estimates of 400 to 500 percent. Groundwater levels drop 6 to 8 metres annually, and the aquifer is estimated to run dry by around 2030.
The tower houses of Sanaa are multi-story buildings typically built from stone and fired brick, reaching up to 8 stories in height and decorated with geometric patterns and plaster openings. They traditionally housed a single extended patrilineal family, with new floors added as sons married, and the uppermost story, called the mafraj, serves as a reception room for afternoon qat chewing sessions.
The Kingdom of Saba founded Sanaa in the 1st century CE as a secondary capital, while its primary capital stayed at the oasis of Marib. Islamic sources hold instead that Shem, the son of Noah, founded the city at the base of the mountains of Jabal Nuqum after his father's death.