It is a wall built by the New Deal-era Works Progress Administration.
The WPA employed people in useful projects to give them work during the depression. Here we see the work of the WPA from 73 years ago.
I use this picture to make the point that where our collective efforts end can be where things begin to slide apart.
At the same time, this website is the result of individual effort. There are times when we must pursue goals by ourselves.
The point here is a rough balance between collective efforts and the efforts of the individual, with a gentle deference to the fact that we are often at our best when we work together for a hopeful common purpose.