“Mount Everest is the tallest mountain in the world.”

Many people readily identify Mount Everest as the tallest mountain in the world, a common belief rooted in how we typically measure such colossal landforms. This widespread understanding often comes from focusing solely on a mountain's elevation above sea level, a practical and visually intuitive way to compare peaks that visibly dominate the skyline. For centuries, explorers and cartographers have used sea level as a universal baseline, making Everest's impressive stature of 8,848.86 meters (29,031.7 feet) above this point an undeniable and easily grasped record.

However, a different perspective reveals a truly colossal contender: Mauna Kea in Hawaii. While its summit only reaches 4,207.3 meters (13,803 feet) above sea level, the vast majority of this shield volcano is submerged beneath the Pacific Ocean. When measured from its base on the ocean floor to its peak, Mauna Kea stands approximately 10,205 meters (33,480 feet) tall, making it significantly taller than Mount Everest in total vertical height.

The reason for the enduring myth lies in this distinction of measurement. When we look at a mountain, our eyes naturally perceive what rises above the water or land around it. The concept of a mountain extending thousands of meters underwater is less apparent and therefore less commonly considered in everyday discussion. This focus on visible height above sea level has cemented Everest's reputation, even though a more comprehensive geological measurement tells a different story about the true giants of our planet.