I wanted to make a gallery to collect all the photographs of benchmarks and sub-type markers here on SummitPost. It was a surprise to find over 600 such images. This page won't get into the history of USGS markers because peakhugger has alread done a good job of that. Make sure to see his article On Bench Marks History which was featured on the front page.
Also, many thanks to Dean who has more to offer to this album than anyone else. Check out his Benchmark Gallery here: My Benchmarks.