Q. Consider the following countries:

• Bolivia
• Brazil
• Colombia
• Ecuador
• Paraguay
• Venezuela

Andes mountains pass through how many of the above countries? (UPSC Prelims 2025)
Answer: Only four
Notes: The correct answer is [C] Only four. The Andes Mountains, the world’s longest continental mountain range, run along the western edge of South America, passing through seven countries in total.

• Bolivia (Correct): The Andes are widest here, home to the Altiplano (high plateau) and major peaks like Illimani.
• Brazil (Incorrect): Brazil is located on the eastern side of South America. Its geography is dominated by the Amazon Basin and the Brazilian Highlands, but it does not contain any part of the Andes.
• Colombia (Correct): The Andes branch into three distinct cordilleras (ranges) within Colombia: the Cordillera Occidental, Central, and Oriental.
• Ecuador (Correct): The range runs through the center of the country, featuring famous volcanic peaks such as Cotopaxi and Chimborazo.
• Paraguay (Incorrect): Paraguay is a landlocked country in the center-south of the continent, characterized by grassy plains and low-lying forests, far to the east of the Andean chain.
• Venezuela (Correct): The Andes terminate in the northern part of South America, with the Venezuelan Andes (Cordillera de Mérida) forming a significant extension of the range.

The seven Andean countries are Venezuela, Colombia, Ecuador, Peru, Bolivia, Chile, and Argentina. From the list provided, Bolivia, Colombia, Ecuador, and Venezuela are the four through which the range passes.