Part of Panama's tropical forest, a biodiversity hotspot lying at the crossroads of two continents and two oceans, is up for sale to developers.
Environmental campaigners say the sale of the forest surrounding the Panama Canal is illegal under Panamanian law, but the government disagrees.
Some 27 hectares of land in the former "canal zone" have already been sold, with a further 100 hectares demarcated and awaiting the highest bidder.
Stakes mark land for sale even on a 450-year-old gold trade path
Those plots already sold are due to become luxury villas while others are destined for commercial and industrial development.
The canal zone was handed over with the canal itself by the US in 2000 in a pristine state, and environmentalists thought it would be left untouched.
"The sale of these forests is illegal under at least three laws explicitly banning their sale," said Raisa Banfield, of local campaigning group Defence of Forests.
"Legal maps show that the area is protected from development. This makes a mockery of the laws that grant state protection and sets a precedent starting a chain of deforestation and land development."
However, the Environment Authority told the BBC in a statement that Panamanian law gave officials power to decide how the returned land should be used - for conservation or development.
The statement added that housing constructed on two parcels of land currently on sale would be subject to special restrictions, in order to prevent ecological damage to the neighbouring Camino de Cruces National Park.
After the initial deforestation and flooding to create the canal in 1903, the forest was allowed to grow back abundantly and biodiversity thrived.
The following 97 years of American military control prevented popularisation and development of the zone which stretched for 80km (50 miles) in length and 16km (10 miles) across the canal.
National parks were created to protect forested areas - but it now appears that some of the forested areas are not included in the parks.
Campaigners accuse the authorities of turning a blind eye to initiatives that promote wealth but threaten nature.
Panamanians last year elected a new president, Martin Torrijos, on a ticket of zero corruption and were hopeful that the country's climate of cronyism would become a thing of the past.
"We are asking Torrijos to take a good look at this matter, which began under the last presidency," said Banfield.
By forming a narrow land bridge linking two continents, Panama provides the essential link in a corridor of endangered tropical forest that connects North America to the Amazon.
Nearly half of the canal watershed is already deforested
Despite only occupying 0.05% of the world's land area, it is a major stop over for migratory birds, containing 950 species, twice as many as the entire continent of Europe.
It is also home to the highest diversity of trees on the planet.
"As a bio-geographic meeting point between North and South America and the Pacific and Atlantic Oceans, plant and animal life in this small area of forest is hyper-diverse," says Dr Bill Laurance, an ecologist from the Smithsonian Tropical Research Institute in Panama, who is an authority on the effects of the fragmentation of forests by land development.
"Nowhere is the battle more intense to maintain this corridor than here in Panama because this is the bottleneck where there is intense population pressure through growth of Panama city, Colon and around the canal."
The condemned land not only contains endangered forest but the historical heritage of the 450-year-old Camino de Cruces stone path, part of the Spanish gold trading route from South America.
Much of the path lies under mud and vegetation, however it is still possible to walk parts of the trail that is now disturbed by the marking posts of builders standing wedged between the ancient cobble stones.
Ironically, it could be that commercial pressures will ultimately help to save Panama's forest from development.
The canal generates about $700m per year in revenue, as individual ships pay anything from $80,000 to $250,000 to pass through.
The canal needs the surrounding forests to keep it from silting up
The trees surrounding the canal are crucial to keeping the 100km (65 miles) of waterway clear of silt and obstruction and full of freshwater.
"The canal system is fed by rainwater which is produced by the forests and enters the canal through the Chagres river," says Dr Michael Roy, of the Conservation Research Education Action pressure group in Panama.
"The trees and roots act as a sponge slowly releasing the water into the canal, which is important during the three-month dry season when the canal is dependent upon rainfall from the previous rainy season."
Nearly 50% of the canal watershed is already deforested, and this figure is rising fast.