Welcome to the National Marine Sanctuary System!

Stellwagen Bank National Marine Sanctuary, MA

Designated: 1992

Size: 846 square miles

 Stellwagen Bank National Marine Sanctuary  is located at the mouth of Massachusetts Bay, about 25 miles east of Boston. The sand and gravel plateau that gives the sanctuary its name was formed by the slow retreat of massive Ice Age glaciers, which sculpted the dynamic seafloor. The nutrient-rich waters above and around the bank support a diverse ecosystem that has been a famous fishing ground for more than 400 years and claims status as the birthplace of East Coast whale watching. Historic New England shipping routes cross the sanctuary, and over the course of centuries, the seafloor has become a repository for shipwrecks--time capsules of our maritime heritage. Visitors can enjoy  whale watching ,  bird watching ,  diving , and  fishing  in this history-rich and biologically-diverse habitat. Make sure to seek out a  Whale SENSE recognized operator .

Mallows Bay-Potomac River National Marine Sanctuary, MD

Designated: 2019

Size: 18 square miles

At  Mallows Bay-Potomac River National Marine Sanctuary , the synergy of history and nature provide a truly unique experience. There’s something for everyone, whether you prefer to walk the shore, view wildlife, fish, or paddle the waters. The remnants of more than 100 World War 1-era wooden steamships--known as the Ghost Fleet--emerge at low tide and provide habitat important to osprey, bald eagles, herons, and an array of flora and fauna.  Mallows Bay County Park  (Charles County, Maryland) provides direct access to the sanctuary and most of the Ghost Fleet remains.

Monitor National Marine Sanctuary, VA/NC

Designated: 1975

Size: 1 square mile

 Monitor National Marine Sanctuary  was designated as the nation's first national marine sanctuary on January 30, 1975. The site was named for the wreck of USS Monitor, a Civil War vessel lost in 1862 deep beneath the ocean surface off the North Carolina coast. Monitor is most famous for engaging the CSS Virginia in the Battle of Hampton Roads, where iron met iron for the first time. Monitor was a prototype for a class of Civil War ironclad, turreted warships that significantly altered both naval technology and marine architecture in the 19th century and contained all of the emerging innovations that revolutionized warfare at sea. Through a combination of education, archaeology, marine science, and regulatory programs, sanctuary staff conserve and preserve the rich maritime heritage of North Carolina’s Outer Banks. Visitors can enjoy the many attractions of partner museums  The Mariners Museum , located in Newport News, Virginia and the  North Carolina Maritime Museum  at Cape Hatteras. A virtual  Outer Banks Maritime Heritage Trail  shares more stories of the amazing natural and cultural history of the Outer Banks.

Gray's Reef National Marine Sanctuary, GA

Designation: 1981

Size: 22 square miles

 Gray's Reef National Marine Sanctuary  protects a vibrant, hard-bottom area off the Georgia coast. The reef’s scattered rocky outcroppings and ledges provide homes for an abundance of marine life. Soft corals, sponges, clams, sea squirts, and other organisms form a dense carpet of living creatures, covering the nooks and crannies of Gray's Reef and giving it the name “live bottom." The reef attracts a diverse array of invertebrates and fish, including crabs, lobsters, black sea bass, snappers, groupers, and mackerels. Loggerhead sea turtles, a threatened species, forage and rest year-round at Gray's Reef, and the reef is within the critical habitat and only known winter calving ground of the highly endangered North Atlantic right whale. The 22- square-mile sanctuary is the only protected natural reef in the Atlantic Ocean between North Carolina and northern Florida. The  Savannah History Museum , one of America's top vacation destinations, offers Gray's Reef on the Run, an interactive exhibit that includes virtual dives to Gray's Reef. Take a selfie while you listen to the sounds of snapping shrimp and other sea creatures "talking" in the reef, and learn about the wonders of the ocean just off the Georgia coast! 

Florida Keys National Marine Sanctuary, FL

Designated: 1990

Area: 3,803 square miles

 Florida Keys National Marine Sanctuary,  best known for its coral reefs, supports one of the most diverse assemblages of underwater plants and animals in North America. The shallow, nearshore waters contain interconnecting and interdependent marine habitats that include fringing mangroves, mudflats, seagrass meadows, hard bottom regions, patch reefs, and bank reefs. This complex marine ecosystem is the foundation for the tourism and commercial fishing-based economies that are so important to Florida. Encompassing more than 3,800 square miles of marine water surrounding the Florida Keys, this sanctuary supports more than 6,000 species of marine life and protects shipwrecks and other important pieces of American maritime heritage. Stop by the  Florida Keys Eco-Discovery Center  in Key West to learn more about the sanctuary.

Visitors to the sanctuary  are encouraged to enjoy the many recreational activities  it has to offer, including world-class diving, swimming, snorkeling, fishing, and kayaking. Seek out our  Blue Star  recognized operators! Maritime history buffs looking for something extra? Check out the  shipwreck trail  that offers nine different wrecks (for beginner to more advanced divers) and the stories that they have to tell us.

Flower Garden Banks National Marine Sanctuary, TX/LA

Designated: 1992

Area: 56 square miles

 Flower Garden Banks National Marine Sanctuary  is located 70 to 115 miles off the coasts of Texas and Louisiana. The sanctuary includes vibrant coral reefs perched on top of underwater mountains called salt domes. Devoted fans of the sanctuary say it's like having a little piece of the Caribbean in the northern Gulf of Mexico! The shallow coral reefs on top of the salt domes represent the most studied and visited portions of the sanctuary, but only account for about 1% of the area within the sanctuary’s boundaries. Deeper beneath the surface (from 98 to 492 feet), lies a unique coral habitat--mesophotic coral ecosystems. The mesophotic corals provide a connection between shallow stony corals and deep-sea corals, and also provide habitat for a variety of commercially and recreationally valuable fish.Visitors to the sanctuary can enjoy diving and fishing in the rich habitat that lies beneath the surface. Check out these charter operators who can take  divers  and  anglers  out to the sanctuary.

Channel Islands National Marine Sanctuary, CA

Designated: 1980

Area: 1,471 square miles

The waters around the five islands of  Channel Islands National Marine Sanctuary  combine warm and cool currents to create an exceptional breeding and feeding ground for many species of plants and animals. Forests of giant kelp are home to numerous populations of fish and invertebrates. Every year, over 27 species of whales and dolphins visit or inhabit the sanctuary including blue, humpback, gray, and sei whales, and Pacific white-sided and bottlenose dolphins. On the islands, seabird colonies and sea lions flourish, while overhead brown pelicans and western gulls search the water for food. The sanctuary is located 25 miles off the coast of Santa Barbara, California. Visitors can enjoy recreational opportunities such as tidepooling, diving, snorkeling, fishing, kayaking, boating, and experiencing Channel Islands National Park. Take advantage of the friendly and knowledgeable  Channel Islands Naturalist Corps  volunteers, who lead tours on whale watch vessels and island hikes at Channel Islands National Park throughout the year.

Monterey Bay National Marine Sanctuary, CA

Designated: 1992

Area: 6,094 square miles

 Monterey Bay National Marine Sanctuary  was designated and protected as a national marine sanctuary in 1992. This vast area stretches almost 300 miles north to south, extends an average of 35 miles offshore, and encompasses more than 6,090 square miles. The sanctuary manages recreational and commercial uses and protects natural resources, water quality, habitats, and its bountiful resident and migratory marine life. In the southern half, visitors will find a mostly undeveloped shoreline of rocky cliffs and steep mountainsides. The northern shoreline is similar but is dotted with settlements of small towns and moderate-size cities. Visitors can enjoy all kinds of  outdoor activities , including surfing, diving, snorkeling, tidepooling, and camping. Additionally, visitors can view the stunning coastline by hiking, biking, and touring by car. Multiple locations accommodate visitors, including the  Sanctuary Exploration Center  in Santa Cruz, located steps away from the famed Beach Boardwalk, and the  Coastal Discovery Center , located at William Randolph Hearst Memorial State Beach on beautiful San Simeon Bay.

Cordell Bank National Marine Sanctuary, CA

Designated: 1989

Area: 1,286 square miles

 Cordell Bank National Marine Sanctuary  is a lush feeding ground for many marine mammals and seabirds. During the spring and early summer, upwelling brings cold, nutrient-rich water toward the surface, causing an explosion of biological activity. Algae and invertebrates thrive in the nutrient-rich water, which attracts a vast array of fish and marine mammals for feeding. Humpback whales, Pacific white-sided dolphins, Dall's porpoises and California sea lions can be seen throughout the summer and fall. However, outside of photos and videos, few people have seen this special part of offshore California due to its depth, currents, and distance from the mainland. An online  video gallery  helps show the public the wonder that lies just offshore. You can also dive into the depths of the sanctuary without getting wet by visiting an  expansive, permanent exhibit  at the vibrant Oakland Museum of California. Visit the Sanctuary's  Ocean Exploration Center  at the Point Reyes National Seashore Lighthouse Visitor Center to get to the edge of the continent, take in the ocean smells and sounds, and gaze towards the sanctuary offshore.

Greater Farallones National Marine Sanctuary, CA

Designated: 1981

Area: 3,295 square miles

Just off San Francisco are major feeding and breeding grounds for 36 species of whales, dolphins, porpoises, seals and sea lions; huge seabird populations, and valuable fisheries.  Greater Farallones National Marine Sanctuary  protects 3,295 square miles of ocean and estuaries. The sanctuary surrounds and sustains the nearly half-million breeding seabirds of the Farallones National Wildlife Refuge - the largest rookery in the contiguous United States. Diverse habitats invite many different activities, from coastal and offshore whale watching and birding, to tide pooling, outer coast and estuary kayaking, and surfing. Check out the sanctuary's  visitor page  for more information. For virtual explorations come to the Farallones  Sanctuary Visitor Center  on Crissy Beach in the Presidio of San Francisco. The  California Academy of Sciences  in Golden Gate Park offers a three-story aquarium showcasing Farallones marine life, and touch tank experiences.

Olympic Coast National Marine Sanctuary, WA

Designated: 1994

Area: 3,189 square miles

 Olympic Coast National Marine Sanctuary  includes the longest stretch of wilderness coast in the lower 48 United States and is unmatched in pristine nature, timeless landscapes, and sublime serenity. The sanctuary protects a productive upwelling zone, home to dozens of marine mammals and seabirds. Along its shores are thriving kelp and intertidal communities, teeming with fish and other sea life. Communities of deep sea coral and sponges dot the dark seafloor and form habitats for fish and other important marine wildlife.

Sharing the 135 miles of coastline with Washington Coastal Treaty Tribes, Olympic National Park, and Washington State Parks, the sanctuary offers visitors a  wide variety of activities  ranging from cultural enrichment to ecosystem exploration. Visit the  Olympic Coast Discovery Center  in Port Angeles to learn more.

Hawaiian Island Humpback Whale National Marine Sanctuary, HI

Designated: 1992

Area: 1,366 square miles

More than half of the humpback whales in the North Pacific seasonally use the waters around the Hawaiian Islands as their principal breeding and calving wintering ground. The  sanctuary 's mission is to protect Hawai‘i humpback whales and this extremely important habitat through closely aligned education, research, and resource protection efforts. In addition to the magnificent whale watching opportunities, the sanctuary also provides popular sites for diving, snorkeling, and surfing.

Humpback whales are here from December to April. You'll also get a chance to see monk seals, dolphins, manta rays, green sea turtles, and white-tip sharks. Visitors in winter months may be able to participate in the  Sanctuary Ocean Count , an outreach and citizen science project created to promote public awareness about humpback whales, the sanctuary, and shore-based whale watching opportunities in the Hawaiian Islands. Make sure to stop by the  visitor centers  on Maui and Kaua‘i.

Papahānaumokuākea Marine National Monument, HI

Designated: 2000

Area: 582,578 square miles

The  monument  is one of the largest conservation areas in the world, protecting an expansive area of the Pacific Ocean. The 1,350-mile stretch of coral islands, seamounts, banks and shoals supports a dynamic habitat containing an incredible diversity of coral, fish, birds, marine mammals and other flora and fauna, many of which are unique to the Hawaiian Island archipelago. Many of the islands and shallow-water environments are important habitats for rare species such as the threatened green sea turtle and the endangered Hawaiian monk seal. On less than six square miles of land, over 14 million seabirds representing 22 species breed and nest. Papahānaumokuākea is of great importance to Native Hawaiians, with significant cultural sites found on the islands of Nihoa and Mokumanamana, both of which are on the National and State Register for Historic Places. 

Public access to the monument is restricted so outreach efforts are focused on bringing the monument to the public. The  Mokupāpapa Discovery Center  Hilo on the island of Hawai'i uses beautiful and interactive, state-of-the art exhibits and a 3,500-gallon saltwater aquarium to “bring the place to the people” and inspire greater appreciation for their fragile ecosystems and unique cultural history. A  virtual visit  to this treasured monument is also available.