SIMI VALLEY, Calif. (AP) - Nancy Reagan returned Sunday to former President Reagan's hilltop grave site, resting her hand on the headstone and leaving a fresh bouquet of white roses on the first anniversary of his death.

She and daughter Patti Davis visited the grave at the Ronald Reagan Presidential Library about 11 a.m., leaving before a public ceremony held later in the afternoon.

About 500 people attended the afternoon ceremony, which lasted 10 minutes. There was a moment of silence, two buglers played and hundreds of tiny American flags fluttered on the lawn.

Reagan's son Michael attended a commemoration aboard the president's namesake aircraft carrier, the USS Ronald Reagan. After a moment of silence, an honor platoon of sailors brought out a floral wreath that was placed beneath a portrait of the 40th president.

In an interview last month, Michael Reagan, a talk radio host, said "not a day goes by that someone doesn't call the show to praise him. He was respected by so many people."

Nancy Reagan's quiet moment of reflection Sunday was in contrast to the days of public mourning that followed her husband's death on June 5, 2004.

Reagan died at 93 at his Los Angeles home from pneumonia complicated by the Alzheimer's disease that progressively clouded his mind. He had told the world of his illness in 1994, five years after ending his two-term presidency.

At the library Saturday, 60-year-old Linda Sturges was among those who gathered to recall the former president. A year ago, she joined thousands of mourners who waited hours to see Reagan's flag-draped casket at the library, though she never made it due to the lines.

"I thought so much of Ronald Reagan," the former elementary school teacher said. "He was a really caring, honest man who loved his country."