Victor Vescovo is the first person to reach the bottom of Earth’s four deepest ocean trenches.

Over the past few months, Vescovo, a St. Mark’s School of Texas alumnus, ventured to the San Cristobal, Santa Cruz, New Hebrides and Kermadec Trenches in the South Pacific.

On Dec. 12, Vescovo tweeted that he completed the first human dive to the bottom of the Kermadec Trench, located northeast of New Zealand. Submersible instruments measured the maximum depth reached to be 10,003 meters.

The Kermadec Trench is the Earth’s fourth-deepest trench. In the past, Vescovo has dived to the bottom of the Mariana Trench (called the Challenger Deep), the Tonga Trench (Horizon Deep) and the Philippine Trench (Emden Deep).

At the start of December, Vescovo had completed a 9,142-meter dive to the Santa Cruz Trench aka North New Hebrides Trench. In the cracks of the canyon walls, he spotted gold-colored bacterial mats feeding off gases and chemicals seeping through.

About five days later, he reached the bottom of the New Hebrides Trench, at 7,794 meters.

Vescovo finished the first crewed descent to the bottom of the San Cristobal Trench, south of the Solomon Islands, in late November. A jellyfish was seen at a depth of more than 8,400 meters below the surface.