The meridian 23° east of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, the Atlantic Ocean, Europe, Africa, the Indian Ocean, the Southern Ocean, and Antarctica to the South Pole.
The 23rd meridian east forms a great circle with the 157th meridian west.
The Thracian Sea is the northernmost part of the Aegean Sea. It is bounded by Macedonia and Thrace as well as northwestern Turkey. It connects to the Black Sea through the Dardanelles Straight, the Marmara Sea, and the Bosphorus Straight.
The entire area of the sea lies north of the 40th parallel. Its length from east to west is from 23°E to about 25.8°E, or from the Strymonian Gulf east to the northernmost part of the Gallipoli peninsula and the width from north to south is about 40.25°N to 41°N, or from the Dardanelles north to the boundary between the Xanthi and the Rhodope regional units.
The meridian 157° west of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, North America, the Pacific Ocean, the Southern Ocean, and Antarctica to the South Pole.
The 157th meridian west forms a great circle with the 23rd meridian east.