This puzzle begins in Merryman Park and ends in a bit of Gunpowder Falls State Park. Both are small. Neither has boundary markers. I hope some of you use bikes on the Northern Central Trail.
Merryman Park is small, although it is on both sides of the road and both sides of the Gunpowder Falls. The boundaries are not marked. You will be there just long enough to find the first stage and learn the coordinates for the final stage. Then park by the Trail and walk along it until you get near. It doesn't matter which side of the rocks you climb. You'll see a passageway to the cache from both sides.