Kalan Mosque - in the center of Bukhara:
The historic center of Bukhara:
The tower structure shown above is the Great Minaret - Kalyan Minor - and was built in 1123.
Reading about this minaret (click the link on the name above), it is also called Tower of Death because criminals would be thrown to their death from the top. Ghengis Khan even ordered the tower to be spared when all surroundings were destroyed - apparently because he was so impressed by the tower. Wow!
I think this is the Nadir Divan-Beghi Madrasah within the Lyab-i Hauz area:
Arabic calligraphy and beautifully detailed tiling: