In terms of shape, Europe is a collection of connected peninsulas and nearby islands. The two largest peninsulas are mainland Europe and Scandinavia to the north, divided from each other by the Baltic Sea. Three smaller peninsulas—Iberia, Italy, and the Balkans—emerge from the southern margin of the mainland. The Balkan peninsula is separated from Asia by the Black and Aegean Seas. Italy is separated from the Balkans by the Adriatic Sea, and from Iberia by the Mediterranean Sea, which also separates Europe from Africa. Eastward, mainland Europe widens much like the mouth of a funnel, until the boundary with Asia is reached at the Ural Mountains and Ural River, the Caspian Sea, and the Caucasus Mountains.