The verdant mountains jut sharply down into the sparkling, languid water of the Coa River in northeastern Portugal. Local fishermen spend the day relaxed on its banks while shepherds herd their goats along steep mountain paths above. This idyllic river valley has recently become the focus of a major controversy that has surprised both local residents and the national government.
Just upriver looms a huge, partially completed hydroelectric dam. In about four years the lake created by the dam will flood a site containing the world's oldest outdoor rock engravings. The pictures of prehistoric bison, goats, and other animals carved into the rocks date back an estimated 20,000 years to the Paleolithic era.
So far the government-owned electricity company, Electricidade de Portugal (EDP), has continued construction, arguing the dam is needed to provide 20 percent of the country's future electricity needs. A growing movement inside Portugal demands a halt to the project and creation of an archaeological park instead.
On March 24 Prime Minister Anibal Cavaco Silva proposed formation of a joint Portuguese-UNESCO committee to recommend a course of action to the government. But opponents note that UNESCO has already issued a report calling for suspension of construction. They fear EDP will commit so much money toward the $300 million project that it will be impossible to stop.
''The public opposes the dam and wants to preserve the engravings,'' says archaeologist Mila Simoes de Abreu. ''This is a world-significant site that must be thoroughly studied. Why does the government insist on building a dam?''
The EDP refuses all direct comment to the media, but has issued a series of newspaper ads noting that the dam is vital to preserve water and supply electricity. Once operational, the dam will produce a steady 10 percent profit for the government, according to one ad.
''We made an option for nonnuclear plants,'' says Carlos Encarnacao, head minister of the Home Affairs Ministry. ''We must make [energy] the cleanest and cheapest way.''
EDP maintains it didn't know the archaeological significance of the engravings and was simply following recommendations of an environmental impact report. EDP paid for the government's Institute for Portuguese Patrimony, Architecture, and Archaeology (IPPAR) to study the site. And that's where the controversy began.
The first Paleolithic engravings were found in 1990, but no one knew the extent or significance of the find, according to an IPPAR spokesman who demanded anonymity. IPPAR archaeologists studied the site for five years, detailing 33 Paleolithic engravings spread over some 15 kilometers (9.3 miles). Hundreds more probably exist, according to experts.
In November 1994 IPPAR archaeologist Nelson Rebanda invited Ms. Abreu, one of the country's leading rock-art specialists, to see some of the engravings.
''I argued that these engravings must be preserved and their existence made public,'' Abreu says. ''Nelson was furious, and said that would violate an agreement between IPPAR and EDP. He was so angry, he threw his hat on the ground.'' On Nov. 11, Abreu issued a fax making the findings public for the first time. Local media charged EDP and IPPAR with a coverup.
AS word spread, angry archaeologists circulated a petition calling for the criminal prosecution of IPPAR President Nuno Santos Pinheiro.
IPPAR has a different version of the story. Nelson Rebanda refuses comment, but the IPPAR spokesman says his agency intended all along to make the public aware of the engravings, but needed more time for study. Today IPPAR is working behind the scenes to preserve the engravings, according to agency sources.
Archaeologists say the outdoor rock art will vastly expand knowledge about Paleolithic society, particularly in light of a similar discovery in December of cave art in southern France. That cave contains some 300 colorful paintings of animals. By comparison, Vila Nova de Foz Coa is only one of five known outdoor sites in Europe and covers a much wider area.
According to archaeology professor Vitor Oliveira Jorge, scientists have mostly studied cave paintings. Archaeologists had theorized that the caves were a religious and mystical location. Dr. Jorge says these engravings also have religious significance and are more than simple animal drawings.
''This is the first time we can imagine how Paleolithic man organized symbolically all the landscape in connection with the water, with very strong religious and magical intentions,'' Jorge says. ''This is one of the most important finds in archaeology in all of the 20th century.''
The government's continued effort to build the dam has caused opposition nationwide, and particularly in Vila Nova de Foz Coa. Local residents had at first favored the dam because it was providing some 2,000 construction jobs.
But local junior and senior high school students campaigned to save the engravings, and many residents changed their minds. In a town of 9,000, an estimated 3,000 people showed up to protest the dam when President Mario Alberto Soares toured the site earlier this year. On April 9-11, Vila Nova de Foz Coa will host a ''rock for the rocks'' music concert and protest rally.
Many local residents now favor building an archaeological park in the area, according to Dr. Antonio Sotero, a local leader in the antidam movement. ''That would preserve the engravings for the world, and it would provide more meaningful jobs over the long term.''
Nationally, opposition to the dam is building as well. Some 135,000 people have signed petitions demanding a halt to the dam, according to Abreu. A Feb. 21 opinion poll in the Publico newspaper showed 42 percent favored keeping the engravings while 32 percent favored the dam.
Opposition parties are now supporting the antidam movement, a potentially troublesome development for the Cavaco Silva government, which faces a tough parliamentary election in October.
On March 19, Socialist Party leader Antonio Guterres, who will become prime minister if the opposition wins, called for a suspension of dam construction so the area can be studied. He says continued work ''is a shame. It risks a fait accompli. We would like it to stop as soon as possible.''
Residents of Vila Nova de Foz Coa are optimistic that a combination of domestic protest and international pressure will force an end to the dam project. Portugal's reputation as a modern, European country may hang in the balance.
''The government will kill this project for one very simple reason,'' says antidam activist Dr. Sotero. ''They don't want the world to see Portugal as a third-world country.''