The Chili/Riga area is home to two rare but related bridges. The posted coordinates will take you to a spot where you can view the first bridge and gather some information to help derive the second set of coordinates. There is room on the south side of the road to safely pull over and park your vehicle, though please note the bridge itself is on private property. Please do not go on the bridge without obtaining permission from Mr. Ehrmentraut who lives across the street.
Some of the information required to do this cache can be obtained from the following link: http://historicbridges.org/bridges/browser/?bridgebrowser=newyork/ehrmentraut/ while some information must be obtained at the first waypoint.
The coordinates for the final are N 43° 05.ABC W 077° 48.DEF.
You will need the following information to determine the final waypoint:
A = The last digit of the year the Ehrmentraut Farm Bridge was moved to its present location.
B = 10 - (the original number of truss webs) for this bridge.
C = Using only the silver glyphs - The sum of the two large digits on the telephone pole closer to the road.
D = Again using only the two silver glyphs - The product of the digits plus 2.
E = The number of verticals on a single truss web.
F = The number of broken diagonals.
In the vicinity of parking place for the final you will find a well preserved cobblestone house, built by Joseph Sibley and owned by the Stuart family for more than one hundred years. The house was constructed mostly from field cobbles gathered from the surrounding property. The final, a micro, is wheelchair accessible and provides a view of another historical property in Chili.
You can validate your puzzle solution with certitude.