Depths

What are the greatest depths that mankind has explored?

What if the deepest hole ever drilled started at...…

The Kola Superdeep Borehole (Russian: Кольская сверхглубокая скважина)…

What if the Marianas Trench stretched from…

At 36,201 feet deep, the Mariana Trench is the deepest location on earth. Found in the Pacific Ocean,…