The Caucasus is a largely mountainous region between the Caspian and Black seas. Running from the west-northwest to the east-southeast are two parallel mountain chains: the Greater (or Northern) Caucasus and the Lesser (or Southern) Caucasus. Between the two chains are two funnel-shaped lowlands that open toward the Black and Caspian seas and that connect at their narrowest point, where the Mtkvari River cuts through a small mountain chain that connects the Greater and Lesser Caucasus ranges at the modern-day city of Tbilisi. The western funnel is the contemporary state of Georgia, and the eastern funnel is Azerbaijan. North of the Greater Caucasus the terrain quickly widens, flattens and dries, becoming the Eurasian steppe — home of the Russians, and before them the Mongols and their offshoots. South of the Southern Caucasus, there is no similar transformation. The Lesser Caucasus, as the name implies, are not nearly as steep or stark as the Greater Caucasus, and they soon merge with the rugged highlands of the Anatolian Plateau in the west and the Zagros Mountains in the south. The eastern of the two lowlands directly abuts the northwestern edge of Iran's Elburz Mountains, the domain of the Persians. Mountain regions matter a great deal when great powers struggle over their orientation. The people who live in those regions have their own geopolitics, competing with each other as vigorously as they defend themselves from outsiders. The intermingling of such large- and small-scale geopolitical factors makes mountain struggles fiercer and more complicated than similar struggles over less-rugged regions. These factors make the Caucasus an important area to watch.
