Commemorated on 8 plaques

Photo of John Adams, Abigail Adams, and Abigail Adams bronze plaque
Spudgun67 on Wikimedia Commons
Photo of John Adams and George Washington bronze plaque
Wally Gobetz on Flickr
Photo of John Adams white plaque
Jez Nicholson on Flickr
Photo of Benjamin Franklin, John Jay, David Hartley, and John Adams marble plaque
Monceau on Flickr