Oxford University is older than the Aztec Empire.
Teaching at Oxford existed by 1096. The Aztecs founded their capital, Tenochtitlan, in 1325, more than two centuries later. By the time Europeans arrived in 1519, it was one of the largest cities in the world, and Oxford was already four centuries old.
Oxford does not have a clear founding date, but there is evidence of teaching there by 1096, and it grew quickly after 1167, when King Henry II banned English students from attending the University of Paris. That makes it the oldest university in the English-speaking world.
The Mexica people, whom we often call the Aztecs, founded Tenochtitlan on an island in Lake Texcoco, traditionally dated to 1325. According to legend, they settled where they saw an eagle perched on a cactus, the image that appears on Mexico's flag today. The Aztec Triple Alliance that dominated central Mexico formed in 1428.
Tenochtitlan became an extraordinary city, laid out with canals, causeways, temples and floating gardens called chinampas. When Hernán Cortés and his Spanish forces arrived in 1519, it may have held 200,000 people or more, making it larger than any city in Spain at the time. The city fell in 1521 after a siege, and modern Mexico City was built over its ruins.
The comparison is a reminder that 'old' and 'ancient' are relative. Civilisations we imagine as belonging to a distant past can be younger than institutions still operating today. Oxford students were arguing over Aristotle long before the Aztec Empire rose, and they are still at it after it fell.
Source: Wikipedia — University of Oxford · Text summarised from Wikipedia (CC BY-SA 4.0)