The town of Moulay Idriss Zerhoun is home to a mausoleum (zouiat) that is highly venerated in Morocco: it is the final resting place of Moulay Idriss I, one of the ancient rulers of the Idrisid dynasty. I do recommend that you visit it during your trip to Morocco. Amongst other things, it will give you the opportunity to see and admire its fountain and its traditional zellige (terra cotta tilework).
I liked the ambiance and atmosphere of Moulay Idriss Zerhoun: very laid-back and relaxed, and no tourist shops or vehicular traffic in the town centre. I recommend spending some time strolling around the traditionally authentic souks in the medina quarter. I really liked the town's intertwining little streets, which form a veritable labyrinth through which it is wonderful to wander at will, eventually finding yourself somehow seated at a table at a kebab restaurant, as if by magic!
To get good views out over Moulay Idriss Zerhoun, I suggest heading up to the heights above the town. The large building you'll see, with the green tiled roof, is the zaouiat of Moulay Idriss. It stands dominating the whole town. From there you'll be able to spot the medersa (koranic school) of Moulay Idriss, complete with its cylindrical minaret.
The pretty town of Moulay Idriss Zerhoun is of great importance to Morocco since the tomb of Idriss I of Morocco can be found there . Idriss I was the founder of Idrisid, the first Muslim dynasty of Morocco. Idriss I built this town himself on Mount Zerhoun; the town's features reflect a very impressive Islamic architecture. In fact it revolves around a Medina and it is there you can view a stunning mosque with a green roof. The mausoleum of Idriss I is found inside this mosque. Moulay Idriss Zerhoun makes for a lovely stop-over during a trip to Morocco.
Given the spiritual character of this town, which is reflected through its history, Moulay Idriss Zerhoun is a centre of pilgrimage for Muslims. From the last Thursday in August, religious festivities take place there.