At certain times in the summer, this will be a very high muggle area.
Use the sign at the posted coordinates to solve the puzzle:
Count the number of green "trees" on the East side of the sign. Divide this number by 1000, and add your answer to: N42 53.684
Count the number of spokes on the ships wheel on either side of the sign Divide this number by 1000, and subtract your answer from: W79 14.194
Happy caching, and watch out for soccer balls!