Eurasia (jʊəˈreɪʒə, alsoUK-S@) is the largest continental area on Earth, comprising all of Europe and Asia. According to some geographers, physiographically, Eurasia is a single continent. The concepts of Europe and Asia as distinct continents date back to antiquity, but their borders are arbitrary and have historically been subject to change. Eurasia is connected to Africa at the Suez Canal, and the two are sometimes combined to describe the largest contiguous landmass on Earth, Afro-Eurasia.
Primarily in the Northern and Eastern Hemispheres, Eurasia spans from Iceland and the Iberian Peninsula in the west to the Russian Far East, and from the Russian Far North to Maritime Southeast Asia in the south. Eurasia is bordered by Africa to the southwest, the Atlantic Ocean to the west, the Arctic Ocean to the north, the Pacific Ocean to the east, and the Indian Ocean to the south. The division between Europe and Asia as two continents is a historical social construct, as neither fits the usual definition; thus, in some parts of the world, Eurasia is recognized as the largest of the six, five, or four continents on Earth.
Eurasia covers around , or around 36.2% of the Earth's total land area. The landmass contains well over 5 billion people, equating to approximately 70% of the human population. Humans first settled in Eurasia from Africa 125,000 years ago.
Due to its vast size and differences in latitude, Eurasia exhibits all types of climates under the Köppen classification, including the harshest types of hot and cold temperatures, high and low precipitation, and various types of ecosystems.
In geology, Eurasia is often considered as a single rigid megablock, but this is debated. Eurasia formed between 375 and 325 million years ago with the merging of Siberia, Kazakhstania, and Baltica, which was joined to Laurentia (now North America), to form Euramerica.
This is a list of the longest rivers in Eurasia. Included are all rivers over .