Some of the most striking geographic features result from human engineering. The Panama Canal, a 77-kilometer artificial waterway completed in 1914, connects the Atlantic and Pacific Oceans, eliminating the long voyage around South America. The Suez Canal in Egypt, opened in 1869, is a 193-kilometer channel linking the Mediterranean to the Red Sea and provides the shortest maritime route between Europe and Asia. The Great Wall of China, stretching over 21,000 kilometers including all its branches, is the longest wall ever built, with the most famous sections constructed during the Ming Dynasty.
Extreme weather records and unusual climates define other remarkable places. The highest reliably recorded temperature is 56.7°C (134°F) at Furnace Creek in Death Valley, California, on July 10, 1913. The lowest is −89.2°C (−128.6°F), measured at the Soviet Vostok Station in Antarctica on July 21, 1983. The Dry Valleys of Antarctica are considered the driest place on Earth, having received virtually no precipitation for about two million years, while Mawsynram in Meghalaya, India, is the wettest inhabited place, with average annual rainfall of about 11,871 millimeters. Angel Falls in Venezuela is the world's highest uninterrupted waterfall at 979 meters, plunging from the edge of the Auyán-tepui mountain.
Geography is also defined by distinctive landforms and large-scale natural features. The Tibetan Plateau, the largest and highest in the world with an average elevation above 4,500 meters, is often called the "Roof of the World." The Amazon Rainforest covers about 5.5 million square kilometers across nine South American countries and is the world's largest tropical rainforest. Mauna Loa in Hawaii is the largest active volcano on Earth by volume and area, and measured from its base on the ocean floor it stands over 9,000 meters tall. Coastlines are shaped by peninsulas, landmasses surrounded by water on three sides but connected to a mainland, such as the Iberian Peninsula, the Korean Peninsula, or Florida, and by isthmuses, narrow strips of land connecting two larger landmasses, like the Isthmus of Panama joining North and South America. A strait is a narrow water passage between larger bodies of water—the Strait of Gibraltar separates Europe from Africa, the Bering Strait separates Asia from North America, and the Strait of Malacca is a vital Asian shipping route. Deltas, like the Nile, Ganges, and Mississippi Deltas, form where rivers deposit sediment as they meet slower or standing water, and gulfs are larger and more enclosed bodies of water than bays, though the terms are sometimes used interchangeably. Finally, a continental divide, such as the one along North America's Rocky Mountains, is a high ridge that separates river systems flowing toward different sides of a continent.