As of the dawn of Islam until the detachment of independent sub-states in many parts of Yemen Islamic Caliphate, San‘a’ persisted as the governing seat, who himself is Caliph's deputy in running the affairs of one of Yemen's Three Makhalifs: Mikhlaf San‘a’, Mikhlaf al-Janad and Mikhlaf Hadhramawt. The city of San‘a’ recurrently assumed an important status and all Yemenite States competed to control it.
The Mamelukes arrived in Yemen in AD 1517. Following the collapse of the Mamelukes in Egypt at the hands of the Ottoman Turks, Yemen fell under the Ottoman Rule and during the first Ottoman rule of Yemen between 1538-1635, San‘a’ became the capital of the Ottoman Vilayet and also during the Ottoman second rule 1872-1918. In 1918, San‘a’ was the capital of Imam Yahya, who ruled North Yemen. At the onset of the 1962 revolution which deposed the imamate rule, it became the capital of the Yemen Arab Republic. It was then the capital of unified Yemen in 1990 where it is dubbed as the historical capital of Yemen.
The old, fortified city has been inhabited for more than 2,500 years and contains a wealth of intact architectural gems. It was declared a World Heritage City by the United Nations in 1986. Efforts are underway to preserve some of the oldest buildings, some of which are over 400 years old. Surrounded by ancient clay walls which stand six to nine metres (20-30 ft) high, the old city boasts over 100 mosques, 12 hammams (baths) and 6,500 houses. Many of the houses look rather like ancient skyscrapers reaching several stories high and topped with flat roofs, they are decorated with elaborate friezes and intricately carved frames and stained glass windows.
One of the most popular attractions is Suq al-Milh (Salt Market), where it is possible to buy not only salt but also bread, spices, raisins, cotton, copper, pottery, silverware, and antiques. The majestic seventh century al-Jami'a l-Kabir (The Great Mosque) is one of the oldest in the Muslim world. Bāb al-Yaman "Yemen Gate" is an iconized entry point through the city walls and is over 700 years old.
Sana'a International Airport is Yemen's main domestic and international airport.
"La budda min Ṣanʻāʼ" (San‘a’ must be seen) are famous words first attributed to Imam Muḥammad ibn Idris al-Shafiʼi (768-820) who visited the ancient capital several times.
Many travelers in ancient days were impressed by the beauty of San‘a’. The well-known Yemeni geographer and historian al Hamdani marveled at the cleanliness of the city:
The least dwelling there has a well or two, a garden and long cesspits separate from each other, empty of ordure, without smell or evil odors, because of the hard concrete (adobe and Cob probably) and fine pasture-land and clean places to walk.
It is the city of Yemen - there not being found ... a city greater, more populous or more prosperous, of nobler origin or more delicious food than it...
The British writer Jonathan Raban devotes a chapter of his 1979 book, 'Arabia Through the Looking Glass' to San‘a’. He initially found the city disorienting:
Suddenly in San‘a’ I was in the middle of a real maze. Its walls were oppressively high, its corridors narrow, its noise frightening. ... San‘a’ was functioning exactly as a labyrinth should: it was a close protective hive for insiders; but for an outsider it was a trap with no apparent means of escape.
Later, as he became more familiar with the place, and had made more acquantainces with its residents, he becomes admiring. In one striking sequence where he is invited onto the roof of somebody's home, the cityscape is revealed to him in a different way:
It was like stepping out into the middle of a vast pop-up picturebook. Away from the street, the whole city turned into a maze of another kind, a dense, jumbled alphabet of signs and symbols. The stucco friezes on the towers formed a continuous scrawl of handwriting aa round...You could look at the walls of San‘a’ for a year, finding more and more hidden meanings in them.