This is the Yesil Mescit, the Green Masjid. A masjid is a small prayer hall. This one was built in 1751, the name derives from the green tiles on the roof. It was built for Musabalioğlu Mustafa Bey. It was built in köfeki, a light, spongy stone that hardens with time. A medrese was built two years later, but has not survived.