Which submarine was the first to circumnavigate the Earth?

The USS Triton was the first submarine to circumnavigate the Earth, achieving this historical feat during its submerged voyage in 1960. Under the command of Captain Edward L. Beach, the USS Triton embarked on the journey on February 16, 1960, and completed it on April 10, 1960. This mission was notable not just for its length and the technology involved but also for showcasing the capabilities of nuclear submarines at the time.

The Triton's ability to remain submerged for extended periods allowed it to traverse vast distances without coming to the surface, demonstrating the strategic mobility of nuclear-powered submarines. This mission marked a significant moment in naval history, contributing to the understanding of submarine operations and tactics during the Cold War era.

While the other submarines listed have notable achievements, they did not accomplish the specific milestone of being the first to circumnavigate the Earth under the sea.