The cache is a black magnetic nano roughly 1.5cm cubed.
The given location is the 'Pentelis Avenue' suburban station on the yellow rail line. This line connects with the blue line at 'Doukissis Plakentias', or connects to the green line at 'Neratziotissa'.
You can check your answers for this puzzle on Geochecker.com.
This cache can be solved as part of;
Pyhr 1: Rira gubhtu yvsr vf abg n tnzr vs lbh jnag gb fbyir guvf chmmyr
lbh jvyy unir gb cynl gur Tnzr bs Yvsr.