The coordinates point to a message board that gives information on Ramsinniemi grove. It's a small but very beautiful nature reserve in eastern Helsinki. Don't hurry to cache-boxes, but enjoy your walk in here. And PLEASE keep on trails. The nature in this grove is very sensitive to damage.
Paths are perhaps too narrow and bumpy for pram. You can leave your vehicle at N60°11,525' E25°05,899'. Walking distance from Rastila underground station is about 2,5 km.
Satellite visibility is not the best possible here, but hiding places are quite obvious.
The message board is divided into smaller frames. Let their number be A.
The frame in lower right hand corner presents some interesting berries. Let the number of different species in it be B.
Your next stop is at
N 60°11.xxx'
E 25°05.yyy'
Where
xxx = 1000-28*A-12*B-4
yyy = 1000-7*(A+B)-3
You'll find a small box that contains final coordinates. Coords are written on the lid.
Don't delete final coordinates from your GPSr. You'll need those with Pentagram-5. In logbook there's also crucial clue for Pentagram-4.
The box is a ½ litre Tupperware.
Note! Aggressive wasps have been reported near cache-box at point 2. Use appropriate caution if you're allergic.
Links to other caches in this series:
Pentagram-1
Pentagram-2
Pentagram-4
Pentagram-5