We're searching for a geological rift or valley that's nearly 4,000 miles long as the crow flies. More about crows and other birds in a minute. It's the name of the rift or rift system that we're looking for... This one covers a lot of territory: ?Turkey Syria Lebanon, Israel, Egypt, Sudan, Ethiopia, Eritrea, Kenya, Tanzania Malawi, I think I'm going to lose it there. There are different ecosystems: Antiokia Lake in Turkey, the Hula, Galilee, Dead Sea, Nile, Soda lakes in Kenya." Photo: http://flickr.com/photos/smsm89Photo: http://flickr.com/photos/smsm89 Okay, so you get the idea. This rift stretches out along a north-south axis. You'll find some of Africa's highest mountains and deepest lakes along its path. It also serves as a major migratory route. Hundreds of millions of birds fly over this rift - all the way from southern Africa to southern Asia. It's a birdwatchers delight. Try and name it if you can. A great valley, a geographic rift that extends thousand of miles. That's what we were looking for in today's Geo Quiz. Great Rift Valley: http://flickr.com/photos/74671419@N00/Great Rift Valley: http://flickr.com/photos/74671419@N00/ And the answer is: The Great Rift Valley. This valley contains a chain of lakes and marshes. That makes it a perfect route for millions of birds migrating between Asia and Africa. The World's Quil Lawrence thinks he spotted about 20 thousand of them on recent bird-watching tour in northern Israel.

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