I have driven by this spot many, many, times over the years and always wondered what this stone was about, well maybe you have too. Now you have a reason to stop.
At the posted coordinates is a stone marking the terminal of the Mayhew Turnpike, which runs from here to Bristol. There is parking on either side of the road, but, please be careful crossing the street to see this historic marker. For your safety, I would take a picture and return to your vehicle to do the math.
The final is along Mayhew Turnpike someplace hahaha
A=1, B=2, C=3 etc
N43 44.MHW W71 45.TPK
M=4th letter of the builders last name.
H=3rd letter on the top line of text
W=last number of the year on the bottom + 1
T=Number of letters in the builders first name - 3
P=3rd number of the first year on the bottom
K=3rd number of the second number on the bottom