TEOTIHUACAN, Mexico (Reuters) -- Burning incense and sounding a conch shell horn, residents of an ancient Mexican city protested on Saturday at the construction of a Wal-Mart store on the edge of the ruins.

The sprawling warehouse-style Bodega Aurrera, a unit of Wal-Mart in Mexico, is due to open in December in Teotihuacan, a major archeological site outside Mexico City.

Opponents say it will ruin a way of life that dates back centuries and have taken legal action to stop it, in a fight that gives a grand dimension to the classic battle between big business and small-town values.

"What they are doing in Teotihuacan is destroying Mexico's deepest roots for short-term interests like lower prices," local teacher Emanuel D'Herrera told about a dozen protesters outside Teotihuacan's town hall. "This is the flag of conquest by global interests, the symbol of the destruction of our culture."

Other protesters bearing placards against the "gringo business" entered the town hall and pledged to stay there until the mayor heard them out.

U.S.-based Wal-Mart, the world's biggest retailer, faces increasing opposition in the United States as it stretches beyond its rural roots and into urban areas. Voters in a Los Angeles suburb recently rejected a Wal-Mart supercenter, and other communities have passed ordinances blocking its so-called big-box stores.

The Teotihuacan construction site lies less than a mile (1.6 km) from the gated tourist park housing the main ruins and is visible from atop the Pyramid of the Sun that has defined the skyline for 2,000 years.

Uphill battle

Local activists know they are fighting a steep uphill battle. Wal-Mart Mexico has local and state approval for the store and construction is well under way.

"I support the store, it will save me time and money," said Camilo Olivas, a father of four who works for the federal electricity commission in Teotihuacan.

He drives 10 minutes every two weeks to shop at a Wal-Mart store in another town to find low prices.

But a handful of opponents say Wal-Mart will kill local family-owned enterprises and erode a lifestyle dating back centuries, while sucking income from locals.

They have filed a criminal complaint, charging authorities with acting illegally in approving the project. They filed a civil complaint on the same grounds and asked the nation's rights ombudsman to step in.

Amid rising controversy, Mexico's government this month said a small pre-Hispanic altar was found buried at the construction site. Plans call for preserving the small structure under plexiglass in what will be the store's parking lot.

"Mexico is one of the few places in the world where the seeds of culture and religion remain," said Tim Sikyea, or Lonely Eagle, a Dene Indian from the Northwest Territories in Canada who came to Teotihuacan this weekend for an annual ceremony with indigenous peoples from across the continent.

"When you have big business come in you lose touch with that culture."

No one knows for sure who founded the ancient seat of power and then abandoned it around 600 A.D. The Aztecs later came upon it and named it Teotihuacan (The Place Where Men Become Gods).

Copyright 2004 Reuters.