Azrou where you can go into the cedar forest and see wild apes. After this, you will be heading across the middle Atlas and experience very strong temperature changes and see the amazing lunar landscapes. Another hour or so and you reach the valleys with wonderful gorges and small villages near oases. These will continually be present until Erfoud and Rissani where the scenery progressively becomes drier and drier. The final step from Rissani to Merzouga being a veritable introduction to the Sahara desert with its enthralling dunes and endless plains. At this point you will be less than 50km away from the Algerian border.
Here is a fabulous blog that will give you an idea of what to expect. These guests did not stay at Riad Felloussia in Meknes but they were on an organized tour with Your Morocco Tour which is one of our regular collaborators.