The snow-covered High Atlas Mountains are a striking backdrop to the cityscape. And these are where we are heading. We successfully negotiated the chaotic network of alleyways and roads of Marrakech, find a car hire agency and bargain a good price (bargaining is an inherent part of Moroccan culture). And we're off...!

Okay, well it wasn't that straight forward. The Moroccans are crazy drivers. Absolutely crazy. And they don't seem to like signs. Doesn't everybody know the way? So after a few false starts we finally find the road to Tizi 'n' Test (the high pass over the Atlas Mountains to the Souss Valley).

Heading due south from Marrakesh (we resorted to using our compass for finding the right road!), the road starts to rise and wind between hills, then ravines, and then along steep valley slopes. The road to the Tizi'n'Test pass is a white-knuckle drive up to 2,000m and then a rapid descent into the Souss valley.

We are following the route that Constanti (the Painted Lady expert) took over the Christmas holidays. By tracing the same route a month later and recording butterflies and caterpillars along the way, we are piecing together the story of the Painted Lady in Morocco. What does it do while it's here? Is it only in one part of Morocco or many different areas? How many life cycles does it go through while here? To these and many other questions we are hoping some answers.

The Souss Valley, and more specifically the area around the red-walled city of Taroudant, is the site of the huge population that Constanti found in March 2009 prior to the enormous migration that was experienced across the British Isles. Constanti recorded thousands of individuals within a small area and it was estimated that the population in 2009 grew to thousands of millions. Constanti believes that the Moroccan part of the Painted Lady .... is the bottleneck. And the population explosion in 2009 was the result of good rainfall that year in Morocco. We are excited about visiting this famous Painted Lady site and our minds are full of warm, sunny days chasing butterflies.

On our way over the pass, there is one Painted Lady site for us to visit. It's a small village.... 'Look for mallow and thistle and there you'll find the caterpillars', said Constanti by way of instructions. 'Count the numbers you find and the life stage' he explained. It sounded so easy. But here deep in the Atlas Mountains in a very different country it's very different to the theory. We find thistles and get out our gardening gloves. And we search and search and search. And find nothing. Okay, perhaps we need a different tactic. Out comes the field knife and we hack down a few unsuspecting thistles. After searching thoroughly we are convinced that the Painted Ladies are not here. We stop at another couple of spots but most of the thistles have died back. We find lots of dead thistles and very few green ones. And no Painted Ladies. No adults, caterpillars, eggs or pupae. Not to worry Taroudant is the hotspot. On we go winding our way through the Atlas Mountainsto the Souss Valley.

We don't have much time to think about the lack of butterflies as the rest of the journey over the Atlas Mountains and down into the Souss Valley is taken up with the driving. It is one of the most interesting, intimidating, beautiful, knuckle-whitening, life-threatening journeys we have ever taken - hairpin bends, sheer drops, worn away road, stunning views.... Once we hit the floor of the Souss Valley the trials are still not over. It's now dark and we have been travelling for eight hours. We turn onto the main road to Taroudant. This is quite a busy road. There are cars, scooters, trucks, bicyles, and pedestrians. Road safety doesn't appear to be a priority here. Not one bicycle has lights (and yet they cycle in the middle of the road), not one pedestrian is wearing reflective clothing, and everybody wants to overtake at inopportune moments. On arriving in Taroudant we find a hotel (using very rusty french and lots of gesturing) and go straight to bed. We are thoroughly worn out.