Myanmar occupies 676,578 square kilometers in mainland Southeast Asia, sharing land borders with Bangladesh, India, China, Laos, and Thailand across a perimeter of 6,159 kilometers. The country extends approximately 2,090 kilometers north to south and 925 kilometers east to west at its widest point. This spatial configuration creates pronounced geographic variation between northern alpine zones and southern tropical coastlines separated by more than 20 degrees of latitude.
The Irrawaddy River system defines Myanmar's central geographic structure. The Irrawaddy River itself measures 2,170 kilometers from headwater convergence in Kachin State to its delta terminus at the Bay of Bengal. The river's two principal tributaries, the Mali and Nmai rivers, merge near Myitkyina at approximately 25°N latitude to form the main stem. Annual discharge averages 13,000 cubic meters per second at the delta, with peak monsoon flows exceeding 40,000 cubic meters per second. The Irrawaddy Delta covers roughly 35,000 square kilometers, extending 290 kilometers along the Bay of Bengal coastline and penetrating inland up to 95 kilometers through a maze of distributary channels. Rice cultivation dominates approximately 2.6 million hectares within the delta, making this alluvial plain Myanmar's primary agricultural zone.
The Chindwin River, flowing 1,158 kilometers before joining the Irrawaddy at Myingyan, drains the northwestern highlands. Peak discharge occurs August through October, contributing approximately 20 percent of the Irrawaddy's total flow volume. The Salween River traverses eastern Myanmar for 1,200 of its 2,815-kilometer total length, descending from Tibetan headwaters through deeply incised gorges in Shan State before entering Mon State and exiting to the Andaman Sea near Mawlamyine. The Salween drops approximately 1,200 meters across its Myanmar segment, creating hydraulic gradients too steep for extensive navigation but suitable for 14 proposed hydroelectric dam sites. The Sittaung River runs 560 kilometers through central Myanmar, draining the gap between the Bago Mountains and Shan Plateau before reaching the Gulf of Martaban. These river systems collectively drain approximately 85 percent of Myanmar's landmass.
Hkakabo Razi reaches 5,881 meters in the extreme north of Kachin State near the borders with China and India, making it Myanmar's highest point and the highest peak in Southeast Asia. Measured coordinates place the summit at approximately 28°N 97.5°E. First confirmed ascent occurred in 1996 by a Japanese expedition, though this claim remains disputed; a 2014 Myanmar expedition terminated 30 meters below the summit due to weather. The mountain anchors the northern terminus of the Patkai Range and experiences permanent snowfields above 4,500 meters. Surrounding terrain in Hkakabo Razi National Park encompasses 3,812 square kilometers of alpine and subalpine ecosystems with recorded elevations spanning 4,900 vertical meters from tropical valleys to glacial zones.
The Shan Plateau occupies approximately 155,000 square kilometers of eastern Myanmar at elevations between 900 and 1,800 meters, representing the westernmost extension of the Yunnan-Guizhou Plateau. The plateau surface exhibits rolling topography punctuated by limestone karst formations and tectonic basins containing agricultural valleys. Inle Lake occupies one such basin in southern Shan State at 884 meters elevation, measuring 22 kilometers long and 10 kilometers wide with an average depth of 2.1 meters. Seasonal depth fluctuation reaches 1.5 meters between monsoon maximum and dry season minimum. The lake's surface area expands from approximately 116 square kilometers in April to 158 square kilometers in October. Indawgyi Lake in Kachin State covers 120 square kilometers at 200 meters elevation, making it Myanmar's largest natural lake by area though its maximum depth of 4 meters is substantially less than Inle's deepest soundings of 3.7 meters.
The Arakan Mountains form a 960-kilometer north-south barrier along Myanmar's western margin, separating the Irrawaddy watershed from the Bay of Bengal coast. The range averages 1,800 meters elevation with peaks exceeding 3,000 meters in the north near Chin State. Mount Victoria in Natmataung National Park reaches 3,094 meters at 21.2°N, representing the highest point in the southern Arakan system. The mountains create an orographic barrier that intercepts monsoon moisture from the Bay of Bengal, producing precipitation differentials exceeding 3,000 millimeters annually between windward coastal slopes and leeward interior valleys. The Bago Mountains extend approximately 435 kilometers north-south through central Myanmar, reaching maximum elevations near 2,100 meters and effectively dividing the Irrawaddy and Sittaung river basins. The Tanintharyi Range parallels Myanmar's southeastern coastline for roughly 700 kilometers, separating narrow coastal lowlands from interior watersheds and forming the natural boundary with Thailand.
Myanmar's coastline measures 2,832 kilometers along the Bay of Bengal and Andaman Sea, extending from the Bangladesh border near 21.5°N to the Thai border at approximately 10°N. The Arakan coast north of the Irrawaddy Delta runs relatively straight with limited deep-water anchorages, while the Tanintharyi coast south of Yangon features extensive archipelagic development. The Mergui Archipelago comprises more than 800 islands scattered across approximately 36,000 square kilometers of territorial waters between 9.5°N and 13°N latitude. Lampi Island, the largest at 188 square kilometers, lies roughly 70 kilometers offshore. Most archipelago islands consist of limestone or granite substrates supporting tropical forest cover, with fringing coral reef development along approximately 40 percent of island perimeters. Coastal tidal ranges reach 5.8 meters during spring tides at Sittwe on the Arakan coast, creating extensive intertidal mudflat exposure across the deltaic regions.
Myanmar's administrative geography divides into seven regions, seven states, one union territory (Naypyidaw), five self-administered zones, and one self-administered division. Regions designate areas with Bamar majority populations while states correspond to areas where ethnic minorities predominate. Kachin State in the far north covers 89,041 square kilometers, making it Myanmar's largest state by area. Shan State occupies 155,800 square kilometers of eastern highlands, representing approximately 23 percent of national territory. Rakhine State spans 36,778 square kilometers along the western coast between Bangladesh and the Irrawaddy Delta. Chin State comprises 36,019 square kilometers of mountainous terrain along the Indian border. Kayah State, at 11,733 square kilometers, is Myanmar's smallest state. Kayin State and Mon State occupy 30,383 and 12,297 square kilometers respectively in southeastern Myanmar along the Thai border and Andaman Sea coast.
Mandalay Region encompasses 37,024 square kilometers of central Myanmar, containing the country's second-largest urban area. Sagaing Region covers 93,527 square kilometers northwest of Mandalay, representing Myanmar's largest administrative region. Magway Region occupies 44,820 square kilometers in the central dry zone along the Irrawaddy. Bago Region spans 39,404 square kilometers northeast of Yangon between the Bago and Arakan mountains. Ayeyarwady Region comprises 35,032 square kilometers of the Irrawaddy Delta. Yangon Region covers only 10,171 square kilometers but contains approximately 7.4 million residents, yielding Myanmar's highest population density at roughly 728 persons per square kilometer. Tanintharyi Region extends along 700 kilometers of southern coastline, covering 43,344 square kilometers.