Blue Mosque or The Sultan Ahmed Mosque is an historic mosque in Istanbul. The mosque is popularly known as the Blue Mosque for the blue tiles adorning the walls of its interior. It was built during the rule of Ahmed I.
Barcelona - Ceiling of the Sagrada Familia, Spain. The columns of the interior are a unique Gaudí design. Besides branching to support their load, their ever-changing surfaces are the result of the intersection of various geometric forms.