A year after celebrating its 100th anniversary since rediscovery, Machu Picchu received another wake-up call last month, when UNESCO experts called on Peruvian authorities to take “emergency measures” to stabilize the site’s buffer zone and protect it from pressure as a result of tourism-related development.

The UNESCO team spent a week evaluating Machu Picchu’s state of preservation, focusing on the neighboring town of Aguas Calientes, the site’s closest access point.  As more and more tourists have flocked to visit the Inca citadel, Aguas Calientes has seen a boom in the construction of hotels and restaurants, leaving conservationists fearful of urbanization near the ancient ruins.

“The authorities charged with protecting the archaeological site of Machu Picchu, located in the Cusco region, must take rigorous emergency measures to counter the growing disorganization of Aguas Calientes,” said Nuria Sanz, the head of UNESCO for Latin America and the Caribbean.

This is hardly the first time mass tourism has led to problematic commercial growth around Machu Picchu.  Last July, new entrance rules were introduced to counter overcrowding, with visitor numbers capped at 2,500 per day, but many experts worry that this is still too high a number for the site to survive.  The added pressure of increased access and tourism-related development continues to accelerate.

Tourism is Peru’s fastest-growing and third-largest industry.  Since 2000, no country in South America has seen more tourism growth than Peru, and no cultural heritage site has been more visited than Machu Picchu.  Despite being home to an abundance of extraordinary ancient sites, Peru has yet to diversify its tourism economy, relying on Machu Picchu for an estimated 90 percent of it tourism revenue.

“We have to create a dynamic that permits strict control and regulation, respect for the site, respect for the authorities because of the efforts they are making, respect for the tourists and the services related to their visits,” said Sanz.

Sanz also said she recommended to the Peruvian government that an international panel of consultants and technicians be set up to design and execute plans for the preservation of Machu Picchu.

Click here to visit Machu Picchu on Global Heritage Network (GHN).