Georgia is in the South Caucasus region of Eurasia, straddling Western Asia and Eastern Europe. Georgia's northern border with Russia roughly runs along the crest of the Greater Caucasus mountain range – a commonly reckoned boundary between Europe and Asia. In Philip Johan von Strahlenberg's 1730 definition of Europe, which was used by the Russian Tsars and which first set the Urals as the eastern border of the continent, the continental border was drawn from the Kuma-Manych Depression to the Caspian Sea, including Georgia (and the whole of the Caucasus) in Asia.
Mountains are the dominant geographic feature of Georgia. The Likhi Range divides the country into eastern and western halves. Historically, the western portion of Georgia was known as Colchis while the eastern plateau was called Iberia. Because of a complex geographic setting, mountains also isolate the northern region of Svaneti from the rest of Georgia.
The Greater Caucasus Mountain Range separates Georgia from the North Caucasian Republics of Russia. The main roads through the mountain range into Russian territory lead through the Roki Tunnel between South and North Ossetia and the Darial Gorge (in the Georgian region of Khevi). The Roki Tunnel was vital for the Russian military in the 2008 South Ossetia War.
The southern portion of the country is bounded by the Lesser Caucasus Mountains. The Greater Caucasus Mountain Range is much higher in elevation than the Lesser Caucasus Mountains, with the highest peaks rising more than 5,000 meters (16,404 ft) above sea level.
The highest mountain in Georgia is Mount Shkhara at 5,201 meters (17,064 ft), and the second highest is Mount Janga (Jangi-Tau) at 5,051 meters (16,572 ft) above sea level. Other prominent peaks include Kazbegi (Kazbek) at 5,074 meters (16,647 ft), Tetnuldi (4,974 meters / 16,319 feet), Shota Rustaveli (4,960 meters / 16,273 feet), Mt. Ushba (4,710 meters / 15,453 feet), and Ailama (4,525 meters / 14,846 feet). Out of the abovementioned peaks, only Kazbegi is of volcanic origin. The region between Kazbegi and Shkhara (a distance of about 200 km (124 mi) along the Main Caucasus Range) is dominated by numerous glaciers. Out of the 2,100 glaciers that exist in the Caucasus today, approximately 30% are located within Georgia.
The term, Lesser Caucasus Mountains is often used to describe the mountainous (highland) areas of southern Georgia that are connected to the Greater Caucasus Mountain Range by the Likhi Range. The area can be split into two separate sub-regions; the Lesser Caucasus Mountains, which run parallel to the Greater Caucasus Range, and the Southern Georgia Volcanic Highland, which lies immediately to the south of the Lesser Caucasus Mountains.
The overall region can be characterized as being made up of various, interconnected mountain ranges (largely of volcanic origin) and plateaus that do not exceed 3,400 meters (11,155 ft) in elevation. Prominent features of the area include the Javakheti Volcanic Plateau, lakes, including Tabatskuri and Paravani, as well as mineral water and hot springs. The Southern Georgia Volcanic Highland is a young and unstable geologic region with high seismic activity and has experienced some of the most significant earthquakes that have been recorded in Georgia
The Voronya Cave (aka Krubera-Voronia Cave) is the deepest known cave in the world. It is located in the Arabika Massif of the Gagra Range, in Abkhazia. In 2001, a Russian–Ukrainian team had set the world depth record for a cave at 1,710 meters (5,610 ft). In 2004, the penetrated depth was increased on each of three expeditions, when a Ukrainian team crossed the 2,000-meter (6,562 ft) mark for the first time in the history of speleology. In October 2005, an unexplored part was found by the CAVEX team, further increasing the known depth of the cave. This expedition confirmed the known depth of the cave at 2,140 meters (7,021 ft) (±9 m/29.5 ft).
Two major rivers in Georgia are the Rioni and the Mtkvari.