The Atomic Cities Peace Memorial ceremony drew an estimated 30 people Thursday night to John Dam Plaza in Richland.
The 31st annual event was organized by the World Citizens for Peace and coincides with the anniversary of the bombing of Nagasaki, Japan, 67 years ago.
Plutonium used to make that bomb was produced at Hanford.
"It's worthy to remember this event," Gene Weisskopf of Richland told the Herald. "It gives me a chance to reflect and remember."
Jim Stoffels, chairman of World Citizens for Peace, gave the opening address.
Tri-City musician Dan Myers played a Japanese bamboo flute called a shakuhachi, as well as music on Native American flutes. Mary Hartman, a Tri-City folk singer, also performed.
The Bell of Peace, a gift to the city of Richland from the mayor of Nagasaki, was rung in memory of Americans who died at Pearl Harbor and the Japanese who died at Nagasaki.