Santos added that the complex is surrounded by four large hills: Pilán, Vicús, Chanchape, and Tongo.
"We think that because of its geographic location the complex could have been a place of strategic value," Santos said.
The area containing the pyramids is surrounded by a cemetery that has been looted by grave robbers.
"But the complex itself is intact," Santos said.
Who Were the Vicús?
"The Vicús are very interesting but so poorly understood, given that most of what we know about them is through looted ceramic art," said Steve Bourget, an archaeologist at the University of Texas at Austin.
"This could be an important find, because it is one of the few with monumental architecture. But it is too soon to tell."
Experts say the Vicús ceramic style is similar in some respects to that of the Moche, a fact that has spawned research on the relationship between the two cultures.
The Moche civilization flourished in areas south of the Vicús from around A.D. 100 to 750, producing intricately painted pottery as well as gold ornaments, irrigation systems, and monuments.
(Read about a Moche mummy and pyramid discovered in Peru in 2006.)
The two cultures thrived within a relatively short distance of each other—less than that between Los Angeles and San Francisco—experts point out.
"It is possible that the Vicús for part of its history was closely affiliated with the Moche culture," said Joanne Pillsbury, an archaeologist at the Washington, D.C.-based Dumbarton Oaks, a research institute affiliated with Harvard University.
The discovery of the Vicús pyramids comes as perceptions about the Moche have shifted, she added.
"It was once thought that Moche was a single monolithic state, but people don't think that is true anymore," Pillsbury said.
"It was likely a series of regional or multi-valley kingdoms that shared a broader culture. And Vicús was probably part of that sphere of interaction."
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