Octagon - In geometry, Octagon is a polygon that has 8 sides and 8 angles. That means the number of vertices and edges of an octagon is 8, respectively. In simple words, the octagon is an 8-sided polygon, also called 8-gon, in a two-dimensional plane.
Quick Multi, there are several brick homes in Manchester NH that have 8 sides, Visit each get the house numbers. Add them together then subtract the house number for the 4th octagon house not shown. Place that number in certitude and go to the final. That is at a STOP sign. Another octagon. Or just check each stop sign in Manchester, NH to make the find.
If you were to look at a sky view of the Mast road house from google earth, you would notice a second octagon building behind it. This is a single family home. It has siding. this house number would be the one to subtract.
Mast Rd

Hanover St

Beech St

These are all private residence. Please do not enter the property. Gain the information needed from the sidewalk.
Special thanks to CJ7 for telling me about an archived cache. This cache was a puzzle for the same octagons.
Henry VIII - The Four Houses Of ... GC114YB
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