Alaviyan Dome - Credit: Wikimedia Commons
The Alaviyan Dome (Persian: گنبد علویان) is a 12th century mausoleum in Hamadan, Iran. A green colored dome once decorated the top of the building, as the poet Khaqani refers to be building as "the green dome", but has been destroyed by the passing of time. Read more on Wikipedia
Source: en.wikipedia.org