Earth displays striking contrasts in scale, from the largest continent to the deepest ocean trench. Asia is the largest continent by area at roughly 44.5 million km², while Australia, sometimes grouped with Oceania, is the smallest at about 8.6 million km². Among oceans, the Pacific dominates in size, followed by the Atlantic and then the Arctic, which is the smallest. Russia is the largest country by area at approximately 17.1 million km², and Vatican City is the world's smallest country. India became the most populous country in 2024, and the Tokyo metropolitan area, home to about 37 million people, is the largest city on Earth.
Mountains and oceans hold their own records. Mount Everest rises 8,849 m above sea level, making it the tallest peak on land, while the Mariana Trench in the Pacific reaches roughly 10,935 m below sea level at Challenger Deep. The Andes, stretching about 7,000 km along South America, is the longest continental mountain range, with the Himalayas claiming the highest average elevations. Underwater, the Mid-Atlantic Ridge is the longest mountain chain on Earth. Many of the world's tallest summits cluster within the Himalayas.
Rivers, lakes, deserts, and waterfalls also push the boundaries of scale. The Nile, at approximately 6,650 km, is generally cited as the longest river, though some measurements rank the Amazon longer; the Amazon is unquestionably the largest by discharge volume. The Caspian Sea is the largest enclosed body of water and the largest lake by surface area, though it is saline, while Lake Superior holds the freshwater surface record and Lake Baikal in Russia contains the most freshwater by volume. The Antarctic Polar Desert is the largest desert on Earth overall, but the Sahara is the largest hot desert. Angel Falls in Venezuela drops about 979 m, making it the highest waterfall, while Inga (or Boyoma) Falls on the Congo River is the largest by volume. Greenland is the world's largest island, and the Great Barrier Reef off Australia is the largest coral reef system.
Some places sit at notable extremes of elevation. The Dead Sea shore lies about 430 m below sea level, marking the lowest land elevation on land, and the Maldives is the lowest country by mean elevation. In contrast, Bhutan, in the Himalayas, is the highest country by mean elevation at over 3,200 m, with Nepal close behind. The Atacama Desert of northern Chile is one of the driest non-polar places on Earth, and the Tibetan Plateau, often called the Roof of the World together with the Pamir Mountains, is the highest and largest plateau on the planet.