Sidi Frej's maristane or Fez maristane is Marocco's main and famous maristane. It is Mérinide dynasty's maristane; its rising, apogee and worse growing are close to the extent and further ruin of this dynasty. This maristane was built by Sultan Abou Youssouf Yacoub, about 1286, imitating a merinide's architectural design in shape of Spanish architecture. In another way, Sidi Frej's maristane was a pattern for many other maristanes in Marocco or in Spain. Since the XVe century, the Merinide Sultan Abou Said Othman II must sell every maristane's properties in order to fit out his troops. Then, the maristane became a mad-house. In 1943, maristane's building burnt. A Kissaria was built at the same place and patients were removed to another maristane named Sidi Frej's new maristane at Bab Khoukha.