The Black Sea and Mediterranean Seas are both almost entirely landlocked, with the Black Sea connecting to the Aegean ... deepest parts of the ocean, known as the abyssal plain, varies from place ...

This is only the second manned expedition to the ocean's deepest depths - the first took place in 1960. The earlier descent was made by US Navy Lt Don Walsh and Swiss oceanographer Jacques Piccard.

To reach the bottom of the trench — the most critical aspect of the entire study — the team used a high-tech manned submarine, the Limiting Factor, a deep-submergence ... other popular places, such as ...