The meridian 51° east of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, Europe, Asia, Africa, the Indian Ocean, the Southern Ocean, and Antarctica to the South Pole.
The 51st meridian east forms a great circle with the 129th meridian west.
Starting at the North Pole and heading south to the South Pole, the 51st meridian east passes through:
| Co-ordinates | Country, territory or sea | Notes |
|---|---|---|
| Arctic Ocean | ||
| Russia | Arthur Island, Franz Josef Land | |
| Barents Sea | ||
| Russia | Island of Zemlya Georga, Franz Josef Land | |
| Barents Sea | ||
| Russia | Northbrook Island, Franz Josef Land | |
| Barents Sea | ||
| Russia | ||
| Kazakhstan | ||
| Caspian Sea | ||
| Kazakhstan | Mangyshlak Peninsula | |
| Caspian Sea | Mangyshlak Bay | |
| Kazakhstan | Mangyshlak Peninsula | |
| Caspian Sea | ||
| Iran | ||
| Persian Gulf | ||
| Qatar | ||
| Saudi Arabia | ||
| Yemen | ||
| Indian Ocean | Gulf of Aden | |
| Somalia | ||
| Indian Ocean | ||
| Seychelles | Providence Atoll | |
| Indian Ocean | Passing just west of Farquhar Atoll, Seychelles Passing between the Crozet Islands, French Southern and Antarctic Lands |
|
| Southern Ocean | ||
| Antarctica | Australian Antarctic Territory, claimed by Australia |
|
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