Caspian Sea coastal area consists of the Quaternary deposits, while its shoreline configuration varies in different places. The coasts are smooth and invariable in some places whereas in other places they are tortuous. There are such gulfs as Gizlar, Astrakhan, and Mangishlag, as well as a variety of bays. The peninsulars of Agrakhan, Buzachi, Tub-Karagan and Mangishlag are very interesting. Both Volga and Ural Rivers mouth shorelines are variable and consist of numerous small islands and distributary channels. Caspian middle sector shoreline configuration is characterized by smooth outline. The Absheron Peninsula is located on the western margin of the Caspian Sea, right where the middle and the southern sectors are bordering with each other. To the west of the Absheron Peninsula there are several islands and shoals of the Absheron archipelago. The largest Pirallahi and Chilov Islands. To the south of the Absheron Peninsula there are such islands of the Baku archipelago as Hara Zira, Gum, Chigil, Gil, Garasu, Zanbil, Sangi-Mughan, Dash Zira, Kur Dashy etc. Middle Caspian east shoreline is more tortuous. The most profound feature here is Kazakh gulf with Kandarly bay, as well as Peschany, Rakushechny and Sue spits. The biggest gulf of the sea east margin is Gara-Boghaz-Gol gulf. The origin of the listed islands and some shoals located within the Caspian south sector (Livanovo etc) is associated with the bottom-sea mud-volcanoes activity.

Caspian Sea has about 50 small and large islands that embraces 350sq km area. Some of them have been mentioned above. South off, at the entrance into the Hirkan gulf there are large Ashur and several other small islands. At the beginning of the last century these islands belonged to Tsar Russia that later on February 26, 1921 were transferred to the possession of Iran by the Soviet Government. Due to the sea level fluctuation Ashur-ada Island recurrently joins to the main land through a narrow bar and became an isolated island.

Azerbaijan coastal areas in most places consist of accumulative lowland - Samur-Davachi in the north, southeast part of Kur-Araz Rivers lowland and Salyan plain within its central part, as well as Lancaran lowland in the south.

Shoreline between Samur River mouth and Absheron Peninsula is almost not tortuous. In this shoreline sector only Samur River delta and Gilazi cape come forward insignificantly. South off Gilazi cape shoreline gradually turns eastward and beginning from the close vicinity of Sarigayabashi spit up to Kohna Bilgah (Amburan) spit and passes into north Absheron Peninsula shoreline.

The Absheron Peninsula forms the southeast termination of the Major Caucasus and represents the largest peninsula within the west coastal area (its length exceeds 60km, and its width is about 30km). Its shoreline configuration is tortuous. There are accumulative bays and spits formed by solid rock cropped out to the surface (Kohna Bilgah, Shuvalan, Gurgan etc). Coastal areas around the spits consist of sands that form excellent beaches. The embankment road was built up between the Absheron Peninsula and Pirallahi Island (1941) that transformed former Absheron strait into north and south Absheron bays. 12km long Shah spit is located on the Absheron Peninsula southeast termination.

South off the Absheron Peninsula and up to Kur River delta shoreline is tortuous. Within this shoreline section there are Puta, Sangachal, Alat and Pirsagat capes formed with solid rocks exposed to the surface, and in addition, there is Bandovan cape formed with mud volcanoes solid outbursts, as well as several embayments located between them. Coastal area between Shih and Alat spits consists of hills and elevations up to 400m high. Most of them were originated due to mud-volcanoes activity.

Kur River delta is the largest one within the Caspian west coastal area. Gizilaghage gulf and the same name sanctuary is located between Kur River delta and Sari Peninsula.