In the following picture, downloaded from GoogleEarth, the city centre is indicated by Athinai (Athens) and the cross at 38 02 49 N 23 51 49 E shows the entrance to the Main Building of the Penteli Astronomical Station, in which the meeting will be held.

Enter these coordinates (in the format 38 02 49.8 N 23 51 49.3 E) in GoogleEarth on your computer to center on the building

(GoogleEarth can be downloaded from http://earth.google.com/downloads.html ).