Located opposite the Kalon Mosque is the Mir-I-Arab Madrassah, with it's sparkling blue domes. It still functions as a Madrassah, and traces its origin to the 16th century and the reign of Ubaidullah Khan. The madrassah was named after Mir-i-Arab, who was a Yemeni ruler who was very close to Ubaidullah Khan. As the madrassah is still a working school, tourists aren't allowed very far into the building.