55 years ago, on December 1st, Rosa Parks sat here:

She was actually not in the area reserved for white people, but was asked to move back when the bus crowded with white people. You can read the rest of the story here and see more of the documentation: An Act of Courage, The Arrest Records of Rosa Parks.
Good link to the rest of the story. You also have a good site. I will be following.
Thanks!