"This was the largest newly-found site on the northern sector of the Calakmul Biosphere Reserve, which is uninhabited and protected as a natural park," Šprajc explained for the STA. It took the archaeologists two and a half months to research the whole site, stretching over an area of 22 hectares.

Traces of the lost city were first spotted in aerial images of a vast forested area. Using a stereoscope, the team of researchers was able to observe the images in 3D, enabling them to notice the "fishy" things that protruded out of the landscape, even if covered with tropical forest.

Their research focused on the elite urban parts of the former Maya city, where they discovered plazas and courts, surrounded by buildings, which had probably been connected to the government or served as residences for the Mayan nobility. Temples and ball courts, along with decorative stone slabs, called steles, show that the site played an important political role in this area, he said.

It was a hieroglyphic inscription on one of the steles that inspired the archaeologists to name it Chactun, meaning "Red Rock". "According to tradition, we label new sites with names that allude to some characteristic of the site or to the circumstances surrounding the discovery," Šprajc, Slovenia's only specialist on Mayan archeology, said.

This was the eighth Maya expedition in 17 years for Šprajc, who not only completed his Master's and PhD studies in Mexico, but also used to work for the Mexico's National Institute of Anthropology and History.

Šprajc, who is also interested in archeoastronomy, decided to return to Ljubljana and continue his research here, at the Institute of Anthropological and Spatial Studies. This year, another Slovenian, a couple of Mexican archaeologists and local workers formed his team, along with a German inscriptions expert.

When asked to summarize some of the most interesting impressions from his expeditions, Šprajc said that each had had its own charm, but this year's remained most vivid in his memory, especially because of an abundance of steles, found placed in less prominent positions, where they had been put by the Mayans.

The position of these stones showed that in the time of crisis, during the Late Classic Maya period, the people had not thought of them as important as before.

"We could definitely do some more surface works here, since we don't excavate. We just do the mapping, focusing on the most important buildings of the site, otherwise it would have taken us more than ten years just to map everything," explained the archaeologist, who does not know yet if he will return to the site.

Even though the ruins are part of the Mexican archaeological heritage, the expeditions of this kind are usually not co-financed by Mexico. However, the project, worth approximately EUR 27,000, was funded in part by the National Geographic Society, the Austrian company Villas and the Slovenian travel agency Ars Ionga.