Yep,
That is the cache. But my searching of the Letterbox site shows that there are two mystery Letterboxes in Maine, one of which being:The Ark The other being:The Clean Getaway
Both of which are on "Mt Ararat" which is where "Scott's Sourdough" is also located.
As for my saying that Letterboxing is "weird", probably a bad choice of words, written on shall we say a "warm" moment. They do things different, that's all that was really meant.
PoPPoP_n_Mammie