Today's Geo Quiz takes us to a city that straddles two continents.
The city is Istanbul. Its home to one of the most beautiful religious buildings in the world. The building in question is popular with seagulls.
At night, birds circle its six, soaring minarets. And during the day, the structure's 250 windows let light stream down into the mosque.
Yes, the building we're after is a mosque. It was commissioned by the Ottoman ruler Sultan Ahmet the First. It's officially named after him.
But we're looking for the name by which it's better known. And that name includes a color.
We'll tell you why that is and more... here