Thanks for the feedback! I'll go ahead and include Fort Williams with confidence for now.

One thing I've noticed is that certain historic caches sometimes cross a threshold of consistent traffic... Newer caches sometimes slow down as the "area" cachers all eventually log it, but some of the "oldest in the state" type caches get a more consistent stream of geo-tourists who like to collect stuff like that.

You guys should be very happy/proud that a notable cache tops your list. I'm a little sad when I turn up states for whom the most visited cache is placed at an interstate rest stop.