Visit Us
The Mariana Trench National Wildlife Refuge is located on a remote location and consists of the deepest waters in the world making any potential visitation extremely difficult. Due to its inaccessibility, the region is virtually unexplored. A visitor contact station located in Guam and Saipan provides opportunities for visitors to learn more about the monument, while interacting with staff.
Monument contact stations located both at Guam National Wildlife Refuge – Ritidian Unit, Guam Nature Center and American Memorial Park Amphitheater, Saipan, Commonwealth of the Northern Mariana Islands.
The Nature Center
- Open Wednesday – Sunday from 7:30 a.m. to 4:00 pm and closed for all federal holidays.
- The office may be closed due to weather including high surf and rip tide advisories.
The Amphitheater
- Open Tuesday to Saturday 7:00am to 3:00pm and closed for all federal holidays.
Location and Contact Information
About Us
The Mariana Trench National Wildlife Refuge is located in the Western Pacific 3,520 miles west-southwest of Honolulu, Hawai‘i, and neighboring the Mariana Archipelago.
The crescent-shaped Mariana Trench, stretching approximately 940 nautical miles and 38 nautical miles wide from the northern limit of the U.S. Exclusive Economic Zone in the Commonwealth of the Northern Mariana Islands to the southern limit of the U.S. EEZ in Guam, was designated as part of the Marianas Trench Marine National Monument on January 6, 2009, through Presidential Proclamation 8335. These submerged lands are managed as a unit of the National Wildlife Refuge System in accordance with Secretary’s Order 3284, which created the refuge on January 16, 2009.
The Mariana Trench was created geologically as the Pacific Plate plunged beneath the Philippine Sea Plate and into the Earth’s mantle and contains some of the deepest known points in the global ocean. The Mariana Trench is also recognized by the international scientific community as the oldest place geologically on the floor of any ocean on earth. Due to its inaccessibility, the region is virtually unexplored, and much remains to be learned about its ecological and biological characteristics.
The ocean floor at such depth consists of a type of pelagic sediment known as biogenous "ooze." Biogenic pelagic sediment is composed of the shells (tests, frustules) of microscopic plankton, both animal (zooplankton) and plant (phytoplankton) plankton.
Our Species
The extreme environment of the Mariana Trench National Wildlife Refuge sustains very unique lifeforms unlike any other in the world.
One mud sample taken from Challenger Deep by oceanographers from the Kaiko yielded approximately 200 different microorganisms. It is an extreme environment, under 16,000 pounds per square inch of hydrostatic pressure. The ocean floor at such depth consists of a type of pelagic sediment known as biogenous "ooze." Biogenic pelagic sediment is composed of the shells (tests, frustules) of microscopic plankton, both animal (zooplankton) and plant (phytoplankton) plankton.
Fun Podcast on Mariana Snailfish:
Join this link for the Fish-of-the-Week Podcast where in Season 3; Episode 25, Mariana Trench Park Ranger Jihan Younis and Professor Alan Jamieson were the guests in June 2023, discussing the Mariana Snailfish and deep-sea exploration in the Mariana Trench Marine National Monument.
