Americans ask #wherewereyou on 9/11 anniversary

Updated
A couple pauses pauses along the edge of the North Pool of the 9/11 Memorial during a ceremony marking the 12th anniversary of the 9/11 attacks on the World...
A couple pauses pauses along the edge of the North Pool of the 9/11 Memorial during a ceremony marking the 12th anniversary of the 9/11 attacks on the World...
Justin Lane/Pool/Reuters

Americans turned to social media to share their memories, thoughts, and tributes on the 12th anniversary of the Sept. 11 terrorist attacks.

The City of New York:

The New York City Fire Department:

http://storify.com/msnbc/social-media-reactions-9-11-anniversary

Americans ask #wherewereyou on 9/11 anniversary

Updated