The Czech Republic occupies 78,871 square kilometers in Central Europe without direct ocean access. The country sits at the drainage divide between the North Sea, Baltic Sea, and Black Sea basins. Elevations range from 115 meters above sea level at the Elbe River's exit point near Hřensko to 1,603 meters at Sněžka in the Krkonoše range along the Polish border. The mean elevation stands at 433 meters. Three historical regions define the country's internal geography: Bohemia occupies the western two-thirds within a ring of low mountains, Moravia extends through the southeast, and a small portion of Czech Silesia occupies the northeastern corner around Ostrava.
Bohemia forms a roughly circular plateau surrounded by peripheral mountain ranges. The Ore Mountains (Krušné hory) stretch 130 kilometers along the German border in the northwest, reaching 1,244 meters at Klínovec. The Bohemian Forest (Šumava) extends approximately 125 kilometers along the southwestern frontier with Germany and Austria, with Plechý peak reaching 1,378 meters on the Austrian border and Großer Arber at 1,456 meters just across the German side. The Giant Mountains (Krkonoše) form a 36-kilometer arc in the north, creating the natural boundary with Poland. The Bohemian-Moravian Highlands divide Bohemia from Moravia with rounded hills rarely exceeding 800 meters, though Javořice reaches 837 meters. These surrounding ranges trap most of Bohemia's drainage within the Elbe River basin.
The Elbe River (Labe in Czech) flows 370 kilometers through Czech territory from its source at 1,386 meters on the southern slope of Violík in the Krkonoše to the German border at Hřensko. The river drains 49,933 square kilometers of Czech territory before continuing 724 kilometers through Germany to the North Sea at Cuxhaven. The Vltava River, running 430 kilometers entirely within Czech borders, is the longest river in the country. It rises in the Bohemian Forest at the confluence of Teplá Vltava and Studená Vltava streams near Volary, flows north through Prague, and joins the Elbe at Mělník 30 kilometers north of the capital. Nine cascade dams regulate the Vltava between the Šumava and Prague, creating reservoirs that supply municipal water and hydroelectric power.
Moravia's drainage flows predominantly south and east. The Morava River originates at 1,380 meters on the eastern slope of Králický Sněžník in the Hrubý Jeseník range, flows 246 kilometers through Czech territory, then continues 88 kilometers as the Austrian-Slovak border before joining the Danube at Devín near Bratislava. The Morava drains 26,658 square kilometers within the Czech Republic. The Dyje River, a major Morava tributary, flows 235 kilometers from Austria through southern Moravia, creating deeply incised meanders in Podyjí National Park near Znojmo. The Odra River drains Czech Silesia northward through Poland to the Baltic Sea, though only 131 kilometers of its 854-kilometer course pass through Czech territory, draining 2,280 square kilometers around Ostrava.
The Krkonoše National Park covers 363 square kilometers along the Polish border, established in 1963 as Czechoslovakia's first national park. Alpine tundra above 1,200 meters supports relict species from the last glacial maximum 20,000 years ago, including dwarf pine (Pinus mugo) and matgrass (Nardus stricta) communities. Sněžka (1,603 meters) receives a Czech-Polish meteorological observatory at its summit, accessible by chairlift from the Czech side since 1949. The park contains the sources of the Elbe, Úpa, and Mumlava rivers. Average annual precipitation exceeds 1,400 millimeters at higher elevations, with snow cover persisting 150-180 days per year above 1,200 meters. The mountain's exposed position generates extreme winds; the Sněžka observatory recorded 245 kilometers per hour in December 1957.
Šumava National Park, established in 1991, protects 680 square kilometers of the Bohemian Forest. The park extends along 125 kilometers of the German and Austrian borders, with its German counterpart Bavarian Forest National Park creating a contiguous protected area of 900 square kilometers. Elevation ranges from 600 meters in river valleys to 1,378 meters at Plechý. Glacial lakes occur in cirques on north-facing slopes; Černé jezero (Black Lake) reaches 40 meters depth, and Čertovo jezero (Devil's Lake) 36 meters. Norway spruce (Picea abies) dominates at 1,000-1,300 meters, with European beech (Fagus sylvatica) and silver fir (Abies alba) at lower elevations. Bark beetle outbreaks killed extensive spruce stands between 1994 and 2010; park management left 11,000 hectares unmanaged to study natural succession, generating sustained local controversy.
České Švýcarsko National Park covers 79 square kilometers in the northwestern corner where the Elbe exits to Germany. Established in 2000, the park protects Cretaceous sandstone formations eroded into gorges, pillars, and arches. Pravčická brána forms Europe's largest natural sandstone arch, spanning 26.5 meters with a clearance of 16 meters, standing 21 meters high. The formation is approximately 400,000 years old. Edmund Ground-Gerstenbergk built a chalet atop the arch in 1881; it now operates as a seasonal restaurant. The park prohibits climbing on Pravčická brána itself due to erosion concerns, but permits technical climbing on 457 designated sandstone towers elsewhere in the park. The Kamenice River carved two gorges 50-150 meters deep through the plateau; visitors traverse sections by boat during April-October when water levels permit.
Podyjí National Park protects 63 square kilometers along a 40-kilometer stretch of the Dyje River valley near the Austrian border, established in 1991. The river meanders through incised loops with slopes reaching 70 percent gradient. The valley creates a microclimate up to 2 degrees Celsius warmer than surrounding plateaus, supporting thermophilous oak forests and steppe grasslands with species uncommon elsewhere in the Czech Republic. The park contains 75 percent of Czech occurrences of the European green lizard (Lacerta viridis). The adjacent Austrian Thayatal National Park protects 13 square kilometers on the opposite bank; together they form a 76-square-kilometer cross-border protected area. The Dyje here contains the most diverse fish community in the Czech Republic with 44 documented species including European weatherfish (Misgurnus fossilis) and Common nase (Chondrostoma nase).
The Moravian Karst (Moravský kras) encompasses approximately 92 square kilometers of limestone plateau 25 kilometers north of Brno, containing over 1,100 documented caves and gorges. The Punkva River flows 6 kilometers underground through the Punkva Caves system before emerging at the Macocha Abyss, a 138-meter-deep sinkhole. Visitors access 1.3 kilometers of the cave system by walkway and boat during guided tours operating since 1914. Speleologists have mapped 34.7 kilometers of passages in the Amatérská Cave system, making it the longest cave in the Czech Republic. Surface drainage through 600 mapped sinkholes and swallow holes recharges the underground system. The karst aquifer supplies drinking water to Brno. Limestone quarrying has occurred since medieval times; active extraction continues at edges of the protected landscape area established in 1956.