WINGDALE, N.Y. — For 20 years, the 80 brick buildings of what was once the Harlem Valley Psychiatric Center have lain fallow, their weathered faces hidden by untamed vines, their windows buckling, their emerald lawns turning to weeds.

Local residents have long been dismayed at the waste of such a handsome rustic property set in a green valley between two ridges.

Then in the summer, the lawns were mowed, the ivy and brush stripped away, and bulldozers cleared land for a soccer field. A sign appeared: Olivet Center. Townspeople learned that the mysterious new owner of most of the 900-acre property was Olivet University, a small evangelical Christian college of about 250 undergraduates based in San Francisco.

Olivet wanted to open a campus 65 miles north of New York City, not exactly the evangelical heartland, but perhaps a new frontier for attracting believers.