The complex, sprawling like an information-age factory, heralds a substantial expansion of a worldwide computing network handling billions of search queries a day and a growing repertory of other Internet services. And odd as it may seem, the barren desert land surrounding the Columbia along the Oregon-Washington border — at the intersection of cheap electricity and readily accessible data networking — is the backdrop for a multibillion-dollar face-off among Google, Microsoft and Yahoo that will determine dominance in the online world in the years ahead.

Microsoft and Yahoo have announced that they are building big data centers upstream in Wenatchee and Quincy, Wash., 130 miles to the north. But it is a race in which they are playing catch-up. Google remains far ahead in the global data-center race, and the scale of its complex here is evidence of its extraordinary ambition. Even before the Oregon center comes online, Google has lashed together a global network of computers — known in the industry as the Googleplex — that is a singular achievement. "Google has constructed the biggest computer in the world, and it's a hidden asset," said Danny Hillis, a supercomputing pioneer and a founder of Applied Minds, a technology consulting firm, referring to the Googleplex.

The design and even the nature of the Google center in this industrial and agricultural outpost 80 miles east of Portland has been a closely guarded corporate secret. "Companies are historically sensitive about where their operational infrastructure is," acknowledged Urs Holzle, Google's senior vice president for operations. Behind the curtain of secrecy, the two buildings here — and a third that Google has a permit to build — will probably house tens of thousands of inexpensive processors and disks, held together with Velcro tape in a Google practice that makes for easy swapping of components. The cooling plants are essential because of the searing heat produced by so much computing power.

The complex will tap into the region's large surplus of fiber optic networking, a legacy of the dot-com boom. The fact that Google is behind the data center, referred to locally as Project 02, has been reported in the local press. But many officials in The Dalles, including the city attorney and the city manager, said they could not comment on the project because they signed confidentiality agreements with Google last year. "No one says the 'G' word," said Diane Sherwood, executive director of the Port of Klickitat, Wash., directly across the river from The Dalles, who is not bound by such agreements. "It's a little bit like He-Who-Must-Not-Be-Named in Harry Potter."

"Google is like the Borg," said Milo Medin, a computer networking expert who was a founder of the 1990's online service @Home, referring to the robotic species on "Star Trek" that was forcibly assembled from millions of species and computer components. "I know of no other carrier or enterprise that distributes applications on top of their computing resource as effectively as Google."