Twenty-two years ago today, a truck bomb went off outside the Alfred P. Murrah Federal Building in Oklahoma City, Oklahoma, killing 168 people and injuring hundreds. | NBC News

At the time of the Oklahoma City bombing in 1995, the Alfred P. Murrah Federal Building was home to several government offices -- and a daycare. "Oklahoma City" premieres this Tuesday, February 7 at 9/8c on PBS . | American Experience | PBS

From the soft glow of the Chairs to the illuminated branches of the Survivor Tree, the Outdoor Symbolic Memorial is transformed under the night sky. Visit our website to learn more about the elements of the Memorial: MemorialMuseum.com | Oklahoma City National Memorial & Museum

Last night, Family Members, Survivors, and First Responders on our Conscience Committee joined with our Teen Board to place wreaths on each of the 168 chairs in the Field of Empty Chairs. Thank you to Total Environment for providing the wreaths and for helping us place them with care. #BeTheLight | Oklahoma City National Memorial & Museum