Container is not at posted coordinates. Visit the historical sign to collect information and then look both ways and walk to the cache container which is a pill bottle hidden beside a tree.
Container is at N 39 56.XXX W 76 23.YYY although my GPS would float all over the place. Maybe it's the iron and the tree cover.
For XXX, count the number of letters in the two words after wrought on the sign. Multiply by ten.
For YYY, use 0, second digit of date at far bottom of the sign, and second digit of date on first line of description.
There's no geochecker. Coordinates will place you in the tree line across the street across the grass. You could probably cheat and not visit the sign, but that isn't how you play the game.