How deep is the Mariana Trench, the world's deepest ocean trench, in feet?

The Mariana Trench is indeed the deepest part of the world's oceans, with a maximum known depth of approximately 36,000 feet, specifically around 36,040 feet at its deepest point, known as the Challenger Deep. This incredible depth surpasses the height of Mount Everest, highlighting the trench's significance in oceanography and deep-sea exploration.

The answer provided reflects this depth accurately, as it is the closest match to the accepted measurements within scholarly resources. Understanding the extreme depths of the Mariana Trench helps underline the importance of marine science and the challenges faced in exploring the deep sea.