The Caucasus Mountains are a mountain system in Eurasia between the Black Sea and the Caspian Sea in the Caucasus region (Turkish: Kafkas Dağları Azerbaijani: Qafqaz dağları Armenian: Կովկասյան լեռներ Georgian: კავკასიონი Chechen: Kavkazan lämnaš Russian: Кавказские горы).

The Caucasus Mountains include:

The Greater Caucasus Range extends from the Caucasian Natural Reserve in the vicinity of Sochi on the northeastern shore of the Black Sea, generally trending east-southeast and reaching nearly to Baku on the Caspian Sea, while the Lesser Caucasus runs parallel to the greater range, at a distance averaging about 100 km (62 mi) south. The Meskheti Range is a part of the Lesser Caucasus system. The Greater and Lesser Caucasus ranges are connected by the Likhi Range, which separates the Kolkhida Lowland from the Kura-Aras Lowland. In the southeast are the Talysh Mountains. The Lesser Caucasus and the Armenian Highland constitute the Transcaucasian Highland. The highest peak in the Caucasus range is Mount Elbrus in the Greater Caucasus, which rises to a height of 5,642 metres (18,510 ft) above sea level. Mountains near Sochi will host part of the 2014 Winter Olympics.

The Caucasus, also Caucas or Caucasia (for endonyms, see below), is a geopolitical region at the border of Europe and Asia, and situated between the Black and the Caspian sea. It is home to the Caucasus Mountains, which contain Europe's highest mountain, Mt. Elbrus. Politically, the Caucasus region is separated between northern and southern parts.

The northern portion of the Caucasus is known as the Ciscaucasus and the southern portion as the Transcaucasus.

The Ciscaucasus contains the larger majority of the Greater Caucasus Mountain range, also known as the Major Caucasus mountains. It includes Southwestern Russia and northern parts of Georgia and Azerbaijan.

The Transcaucasus is bordered on the north by Russia, on the west by the Black Sea and Turkey, on the east by the Caspian Sea, and on the south by Iran. It includes the Caucasus Mountains and surrounding lowlands. All of Armenia, Azerbaijan (excluding the northern parts) and Georgia (excluding the northern parts) are in South Caucasus.