So, I have always been fascinated with USGS Bench Markers that can be found at the summits of many mountains. I have done a few searches, but really can't find much logistical information on them. I'm hoping someone on this forum may have some knowledge of these and may be able to help. This is purely for my own curiosity (and maybe other forum members).

1. What makes a mountain worthy of one of these markers? I see many mountains that have them and many that do not, but there doesn't seem to be a rhyme or reason to them that I can tell. For instance, I believe Washington, Lafayette and Liberty all of have them, but Osceola and Lincoln do not, why? I've even seen smaller peaks with no real popularity, such as Iron Mountain have them too (although, I think this mountain used to more popular back in the day when it was a ski mountain).

2. Where can I find a list of USGS markers that exist? Is there a database some place that can be accessed on line? I'm wondering more specifically for New Hampshire.

Again, just questions out of curiosity...hoping someone has some insight!