Here is a picture of the path up to the Porta Rosa at Velia (ancient Elea), which Parmenides may have had in mind when he wrote of the Way of Truth. It's certainly hard and rugged enough, especially in the lower sections, where the steps are clearly designed for mules. The verticals are unnecessarily shallow for humans, and the horizontals are the wrong size for any normal human gait. It reminded me very strongly of mule tracks in the Aegean; the same channels for rainwater, the same courses of regular, harder stones at the front edge of each step.
Porta Rosa is later, and I don't know about the buildings, but I'm pretty sure Parmenides would have known the path. It leads from the south harbour up to the acropolis near Porta Rosa and I suppose it must have been the main street of Elea. It is also extraordinarily tiring. At least, I found it so, and I must have been fairly fit at the time as I had walked from the Austrian border.
All the best,