Vietnam has an area of 127,207 square miles (329,465 square kilometers) and is located in Southeast Asia. The country has a coastline of nearly 1,440 miles (2,317 kilometers), much of which fronts on the South China Sea. Border countries are China, Cambodia, and Laos. The latter two countries, along with Vietnam, constituted the former French Indochina.

Northern Vietnam is quite mountainous, especially the extreme north and northwest. The Red River (Song Hong), which originates in China's Yunnan Province, is the principal river of the north and is about 725 miles (1,167 kilometers) in length. The major lowland area is a delta that has been created by deposits from the Red River as it enters the Gulf of Tonkin. The river passes through the capital city of Hanoi. For more than 2,000 years the Tonkin Lowland, considered the cradle of Vietnamese civilization, has been the scene of considerable water control efforts in the form of canals and dikes.

The southernmost portion of the country is dominated by another lowland that is much more extensive than that in the north. This lowland has essentially been created by the Mekong River (Song Cuu Long) and its various tributaries. Just north of Ho Chi Minh City (formerly Saigon) the landscape becomes more varied and rolling with forested hills.

The central portion of Vietnam varies in width but is only 35 miles (56 kilometers) at its narrowest point. This region has only a narrow coastal strip in contrast to the rest of the coastline, where wider lowlands exist.

The westernmost portion of the area is dominated by the Annamese, or Annamite, Cordillera, a major mountain chain, which forms the spine of the country from north to south. Along with the two major rivers, there are many shorter rivers that drain the highlands and flow eastward to the South China Sea. The country also has six island groups, 14 separate mountain ranges, and three large lakes.

The climate of Vietnam is largely tropical, though the north may be distinguished as subtropical. Differences in humidity, rainfall, and temperature are caused largely by changes in elevation. The north has a hot and humid five-month-long wet season lasting from May through September. The remainder of the year is relatively warm and rainfree, but humid. A prolonged period of fog, cloudiness, and drizzle occurs from December through April in the central zone and coastal lowlands. The south is characterized by a monsoon-type climate dominated by a changing wind pattern that brings rainfall. The rainy period is shorter than in the north.

In the north maximum rainfall occurs in July and August, while in the south these peaks are in June and September. Average rainfall at Hanoi is 72 inches (183 centimeters) per year, at Hue 117 inches (297 centimeters), and at Ho Chi Minh City 81 inches (206 centimeters). In the higher elevations of the Annamese mountain chain, rainfall can exceed 175 inches (445 centimeters). The region is subject to typhoons, which may occur from July through November. Daily temperatures in the south range between 64o and 92o F (18o and 33o C), while in the north the climate is considerably cooler. Average summer temperatures are approximately 82o F (28o C) with the winter average at 63o F (17o C).