GREEN HERONS, SNOWY EGRETS, and massive American white pelicans wing across our path and cut through the sky above as we canoe through the canals of Lake Xochimilco in the southern reaches of Mexico City. I am accompanied by Francisco “Paco” Juarez, a biologist from Mexico’s Autonomous Metropolitan University (UAM), who is taking me to one of the chinampas islands that has been restored by the nonprofit Humedalia to something that closely resembles the floating gardens common in the city during pre-Columbian times. It’s a voyage through both space and time to a slightly magical realm.

The chinampas of Xochimilco are a wetland ecosystem of high biodiversity, home to 140 species of migratory birds as well as unique native species like the acocil crayfish and the amphibious axolotl salamander, a small dragon-like creature that occupies an iconic role in the Mexican psyche. They are also protected as a UNESCO World Heritage Site. But the sheer natural abundance alone is not what makes the area special. What’s amazing about this sprawling wetland is that it is entirely manmade and remarkably productive. It’s an agricultural system that once provided almost all the food for the ancient Mexican capital of Tenochtitlan, an island metropolis which was as large as the city of Paris at the beginning of the sixteenth century when the Spanish arrived.

The vast majority of chinampas today are owned and managed by Indigenous families.

When European colonizers decimated the city in the 1500s, the chinampas system had grown to cover most of Lake Xochimilco, the southern reaches of the massive freshwater system that once extended across the entire Valley of Mexico. While the chinampas continued to provide food for the capital of “New Spain,” which was built right on top of Tenochtitlan, some were lost as the lake and wetlands were drained and filled in to accommodate the growth of the city. Many more were converted in the second half of the twentieth century, as the city’s population exploded and expanded into areas previously used for agriculture. Rapid growth also led to increasing soil and water pollution, land subsidence, flooding, and other environmental challenges for the region’s traditional urban farmers.

Still, several outermost reaches of the Xochimilco chinampa system survived, and lately, are coming back to life. The vast majority of chinampas today are owned and managed by Indigenous families who inherited the plots from their ancestors and today sell produce directly to local markets, many in nearby low-income inner-city neighborhoods. Other abandoned chinampas are being restored by groups like Humedalia, part of a movement in Mexico City that is turning to this ancient living legacy as a form of decolonization, a strategy to foster urban food resilience, and an investment in a sustainable future. Today, according to Juarez, the chinampas now provide 15 to 20 percent of the fresh produce for the modern Mexican capital, a metropolitan area of nearly 22 million people, the largest on the North American continent.

The chinampas represent one of the most ingenious, efficient, and ecological urban agricultural systems every invented. The artificial islands were created by pre-Colombian farmers by combining the mineral-rich sludge from the bottom of the lake, which once spanned the Valley of Mexico, with stacked layers of vegetation and then anchoring them with living willow trees. Abundant water allowed up to seven harvests a year, instead of just one — waiting for rain becomes unnecessary when your garden is built right on waterways that also allow for easy navigation between the plots.

As we glide through the canals, which get smaller and smaller around every turn and bend, Juarez explains to me that the abundance of wetland fowl is an indicator that the water is full of fish, and that, in turn, is an indicator that the water is clean and healthy despite all the agricultural activity happening here, and despite the urban setting. Indeed, in addition to providing local food, this agricultural system offers a range of ecosystem benefits, from water filtration to increased biodiversity to greenhouse gas sequestration.

It’s a telling sign that the floating gardens, a living artifact from the past, are outlasting the already crumbling, opulent cathedrals built by the Spanish from the massive wealth extracted from Mexico. The short-sightedness of colonial systems stands in stark contrast to Indigenous systems built in harmony with nature.

“This is more than a relic of the past; this is a living classroom for the future,” Juarez tells me as we finally set foot on solid land to explore the Humedalia chinampas. He explains that during much of the week kids from different Mexico City schools come to the floating garden to take part in planting and harvesting.

“This is more than a relic of the past; this is a living classroom for the future.”

Farming on the chinampas is done using simple hand tools — gasoline powered and electrical equipment is not allowed. Nor are these modern tools needed. The planting and harvesting process is simple here. The unique mineral rich soil of the chinampa, created from the dark sediment of the lake floor, makes growing easy and eliminates dependence on chemical fertilizers. Chemicals would also disrupt the rich wetland ecosystem that surrounds us. These practices stand in stark contrast to modern industrial agriculture and its reliance on intensive pesticide and herbicide use, land-clearing, and monocropping.

I ask Juarez about the axolotl, and he admits to me he has only seen them twice in the four years he has been working here. A unique and mystical animal, the axolotl has the nearly supernatural power to regenerate any body part that is damaged or lost, including its head and even its heart. A fitting totem animal for a magical garden ecosystem that is also making a comeback.

After walking through the lush vegetable and native grain cultivations, where red amaranth and blue corn line the path, we enjoy a lunch made from food grown entirely in the garden, including a heaping salad topped with quinoa and freshly pan-fried empanadas stuffed with squash and beans. Sitting under the shade of willows while overlooking the exuberant farm and the network of canals, with the mountains rising sharply in the background while feasting on the bounty of the floating gardens, it’s hard not to think about their potential elsewhere.

Similar traditional floating garden systems exist on Lake Dal in Kashmir, where they are tended by boatman farmers, and along the River Ganges in Bangladesh, where they rise and fall with the seasons, unaffected by monsoons or flooding. Like the chinampas of Xochimilco, these have provided healthy sustenance to large populations over long periods of time while enhancing the environment. Recently, the chinampas of Mexico City have inspired regenerative agriculture projects around the world in areas where there are large freshwater resources. In South Sudan, the raised islands are being built in flood zones as a way to keep soil above anticipated rain levels so that gardens are not washed away. Along Costa Rica’s swampy Caribbean coast, the Punta Mona Center For Regenerative Design and Botanical Studies is experimenting with them as a way to create sustainable agricultural systems for large water-based cities like Miami.

“Wherever you have freshwater lakes near a big city, chinampa-like systems are conceivable — and this applies for many parts of the world,” says Roland Ebel, a researcher with Montana State University’s Sustainable Food Systems Program. Imagining massive floating garden systems across the globe feeding people and creating wildlife-rich ecosystems at the same time is quite inspiring.

In the here and now, as I sit talking with Juarez, the sun sinks low over the mountains and casts golden rays over the Humedalia chinampas, and I can easily image how a sustainable, decolonized, and re-enchanted Mexico City of the future can rise from this ancient regenerative Indigenous system.