I did part of the Zate/Zat valley earlier this year. The route is tarmac (olive yellow in map below) until Arba Talatast. There's supposed to be some dinosaur footprints to the south west and I tried some tracks (red in map) but couldn't get through. It was only when I got back to the high ground at Talatast that I saw the track I needed heading due west.
Anyway, I went a short way south on another piste (nowhere near as far as you) where there's supposed to be the start of a tunnel that would provide an alternate way through to the south rather than over the Tizi n'Tichka, but then headed back again.
I then tried, successfully, to find the piste to the east that links to the main road over the Tichka. This was easy for about six miles (blue on map) but when I could see the road in the distance far below me the piste suddenly deteriorated and walking on ahead I found part was washed away and impassable to 4-wheel vehicles. I reckoned I could get through on the bike, but it took more than an hour of road building--moving rocks, using stones to fill gaps--to get the bike down the steep slope, then I gritted my teeth and went for what was by then nothing more than a mule track with a severe dropoff.
I'm still here, so obviously made it.
"For sheer delight there is nothing like altitude; it gives one the thrill of adventure
and enlarges the world in which you live,"
Irving Mather (1892-1966)
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