Exterior of the Ismail Samani Mausoleum, which is a historic building in Bukhara, Uzbekistan. It was completed in 905. Its walls are two meters thick. Ismail Samani founded the Samanid dynasty, which was a Persian empire that flourished in Central Asia for a century. It produced luminaries like Abu Ali Ibn-Sina (Avicenna), the medieval world's great medical genius; court poet Rudaki, who founded modern literary Persian; Khorezm, the great astronomer; and Al-Khorezmi, who founded algebra. Photo taken on July 10, 2012.