What was one of the main functions of the Aztec causeways?

The main function of the Aztec causeways was to facilitate transportation over water. The Aztecs built sophisticated causeways that connected their capital, Tenochtitlán, to the surrounding mainland. These causeways were crucial for navigating the extensive lake system in which the city was located. By allowing for the transportation of people and goods across the waterways, they enabled movement between the city and the mainland, enhancing trade and communication. This engineering innovation also played a significant role in the social and economic development of the Aztec Empire, as it allowed for easier access to various resources, markets, and agricultural lands surrounding the lakes.

In contrast, while the causeways may have had incidental military uses or provided access to temples and trade, their primary purpose was indeed the facilitation of transportation across the water, making them essential for the functioning and expansion of the Aztec civilization.