Petén Basin

Listen for a moment. Out past the lake, deep in the green, a low roar rolls through the trees. It sounds like a big cat, or maybe a storm. It is neither. It is a howler monkey, and that sound is the voice of the Petén Basin. The air here is warm and heavy, and it smells of wet leaves and lake water. You are standing at the edge of one of the great forests of the Americas.

So what exactly is the Petén Basin? It is not one building or one ruin. It is a wide lowland region of forest, swamp and limestone. Most of it lies in northern Guatemala, in the department of Petén. Its edges reach into southern Mexico and western Belize. For geographers, it is a single natural unit. For archaeologists, it is something more. This basin was one of the heartlands of ancient Maya civilization.

Start with the ground under your feet. The whole basin sits on limestone. Rain sinks into this porous rock quickly, so the region has few rivers on its surface. Instead, there are seasonal swamps that locals call bajos. They flood in the wet season and dry out in the dry months. Water was always the central problem of life here. The ancient Maya solved it with reservoirs, plastered plazas, and careful channels that collected every drop of rain.

Now look at the island around you. Flores is small, with narrow streets, pastel walls and red-tiled roofs. It sits in Lake Petén Itzá, linked to the shore by a causeway. This island has a remarkable past. Before the Spanish arrived, it held a Maya city called Nojpetén. It was the capital of the Itza people, and their kingdom stood longer than almost any other in the Maya world.

Here is the first surprise. Most of the Maya region fell under Spanish control in the sixteenth century. But the Itza kingdom here in Petén held out until 1697. That is nearly two centuries after Columbus first reached the Americas. The thick forest and the long distances protected it. When Spanish forces finally took the island, the last independent Maya kingdom came to an end. The town you are walking through grew on top of that capital.

But the Itza were late arrivals in a very old story. Much earlier, in the period archaeologists call the Preclassic, large cities were already rising in this basin. The most famous is El Mirador, in the far north near the Mexican border. Its builders raised enormous platforms and pyramids centuries before the birth of Christ. One of its structures, known as La Danta, is among the largest ancient buildings by volume anywhere in the world. Today, reaching it still means a long trek through the forest.

Then came the Classic period, roughly the third to the ninth centuries. This was the age of Tikal, the best-known city of the basin, about an hour's drive north of Flores. Tikal's temples rise above the forest canopy. Its kings fought long wars with Calakmul, a rival city to the north in what is now Mexico. Around them stood many other cities, such as Uaxactun and Yaxha. The basin was crowded with kingdoms, alliances and rivalries.

The second surprise came from the air. In 2018, researchers published the results of a laser survey called LiDAR. Aircraft scanned the forest, and the laser data let scientists see the ground beneath the trees. The results showed tens of thousands of previously unmapped structures. There were houses, terraces, causeways, defensive walls and farm fields. The ancient population of the basin was larger and more connected than many experts had believed. Much of it still lies under the forest, unexcavated.

So what happened to all those people? In the ninth century, many of the great cities of the southern lowlands went into decline. Building stopped. Inscriptions stopped. Over time, many people moved away. Scholars still debate the causes. Drought, war, overpopulation and damage to the land are all part of the discussion. Most researchers now think several pressures worked together. The Maya people did not disappear, though. Their descendants still live across this region today.

After the decline, the forest grew back. For centuries, the basin was one of the least populated parts of Central America. In the twentieth century, workers called chicleros came into the forest to tap sapodilla trees. The sap, called chicle, was the original base of chewing gum. These workers often found ancient ruins on their routes. Some of the trails they cut later guided archaeologists to sites that the outside world had never recorded.

Today, much of the northern basin is protected inside the Maya Biosphere Reserve, created in 1990. The forest here shelters jaguars, tapirs, spider monkeys, and bright toucans. It also faces real pressure from logging, cattle ranching and fires. Local communities, scientists and conservation groups work to balance protection with people's need to earn a living. When you visit a site in the reserve, you are visiting a living forest as much as an ancient ruin.

Look for one tree in particular. The ceiba is tall and smooth, with a straight grey trunk and wide branches near the top. It is the national tree of Guatemala. In Maya belief, a great ceiba stood at the centre of the world. Its roots reached into the underworld and its branches held up the sky. Many farmers still leave ceibas standing when they clear land. You can often spot one alone in an open field.

Now bring your eyes back to the lake. In the late afternoon, the water turns gold and then pink. Small boats move between Flores and the villages on the far shore. Somewhere beyond those low green hills are temples that waited under the roots for a thousand years. Before you walk on, listen again. The birds, the boats, perhaps a distant howler. This is the same basin, and it is still very much alive.