What is the highest mountain entirely within a single country?

Dhaulagiri is the highest mountain entirely within a single country.

Dhaulagiri I rises to 8,167 metres in Nepal, making it the highest of the world's major peaks whose entire mountain lies inside one national territory. It is also the world's seventh-highest mountain and the highest point of the Gandaki river basin.

The name comes from Sanskrit-derived Nepali words meaning “dazzling, white” and “mountain.” Surveyors considered Dhaulagiri the world's highest known mountain in the early nineteenth century, after measurements in 1808. Later surveying established that other Himalayan peaks, including Everest, were higher.

Dhaulagiri is often confused with Everest or K2 because those mountains are taller, but both lie on international borders: Everest between Nepal and China, and K2 between Pakistan-administered territory and China. Manaslu, another listed option, is wholly in Nepal but reaches 8,163 metres, slightly lower than Dhaulagiri. Dhaulagiri was first climbed on 13 May 1960 by a Swiss-Austrian-Nepali expedition led by Max Eiselin.