What are the seven summits

The Seven Summits are composed of each of the tallest mountain peaks of each of the seven major continents. Different lists include slight variations, but generally the same core is maintained throughout. Summiting all of them is regarded as a mountaineering challenge.

Alpinism author Jon Krakauer (1997) wrote in Into Thin Air that it would be a bigger challenge to climb the second-highest peak of each continent, known as the Seven Second Summits—a feat that has not been accomplished as of July 2011.

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