An enormous stone structure pokes above the trees in the midst of a northern Guatemalan jungle. From the air, it looks like some sort of strange, lonely volcano randomly plopped within the vegetation. But the structure is actually one of the world’s largest pyramids, part of the “lost city of the Maya.”

El Mirador, the lost city, thrived from the sixth through third centuries BC. In the following centuries, construction within the city slowed, and its population began to dwindle. It was finally abandoned in the waning days of the ninth century.

In the years since its people left, the jungle swallowed the city’s many stone structures. The site laid dormant for hundreds of years until archaeologists began excavating it in the mid-19th century. Thousands of structures fill the Prehispanic city, but perhaps none are as impressive as the La Danta temple.

La Danta stands a staggering 236 feet tall. It has a total volume of nearly 99 million cubic feet, making it one of the world’s largest pyramids, as well as one of the world’s most enormous ancient structures. It’s been calculated that 15 million man-days of labor were needed to construct the gigantic building. A staircase leads up the temple’s eastern face, rewarding those who climb it with views of a sea of trees that stretches as far as the eye can see.