Flowers and vegetables growing in garden beds on a chinampa at Xochimilco, Mexico City, Mexico - stock photo

At Xochimilco the Aztecs created a network of canals and artificial islands, called chinampas, to be used as agricultural fields. The chinampas were formed in the lakes by first creating a perimeter fence of stakes and interwoven reeds below the waterline, and then filling the interior with soil and vegetation until an island rose above the waterline. Trees were often planted along the island shores to further stabilize the soil.The chinampas enabled the extension of cultivatable land into wetland areas. Xochimilco is now a UNESCO World Heritage site.