A couple of years ago a new hiking trail from Mithi to Karidi has been marked. Regardless wether it is true or not that it already has been used by the minoans, it’s a nice trip anyway.
It’s not an easy walk though. It’s almost constantly a steep incline to Karydi, and the surface consists of the typical stones of alpine hiking trails. I strongly recommend hiking boots instead of sneakers. I took the same way back to Mithi which was much easier than the incline. I thus recommend to visit the “attractions” (like the bat’s cave, the viewpoint and the shepard’s fridge) while returning.
That was a total of about eight kilometres, four hours (including rests) and one and a half litres of water.
The trail is marked by some wooden signposts and red dots sprayed on rocks. I didn’t find a free download of a gpx track, so here’s mine, recorded during the decline from Karydi to Mithi. OsmAND served me very well BTW.