Gulfs are geographical features in which a portion of a sea or ocean is partly enclosed by land. They are created by movement in the Earth’s crust, which forms an opening that is later filled in by nearby bodies of water. Gulfs are often linked to an ocean by a strait, although occasionally they have wide openings that make them appear almost the same as the bodies of water that border them. By definition, gulfs are similar to bays, but there are some nuances between the two — in general, gulfs are larger (though that’s not always the case).
Around the world, you’ll find gulfs of varying sizes, shapes, and depths. Many serve as important trading routes and tourism centers. Curious which gulfs rank above the rest? Here are five major gulfs you should know about.
Gulf of St. Lawrence
The Gulf of St. Lawrence occupies an area of approximately 91,000 square miles in eastern Canada. It acts as an outlet for the Great Lakes as they empty into the Atlantic Ocean. Half of Canada’s 10 provinces border the gulf: Nova Scotia, New Brunswick, Newfoundland and Labrador, Prince Edward Island, and Quebec. Several streams and rivers empty into the gulf’s waters, including the namesake St. Lawrence River. It’s also home to significant islands such as Cape Breton Island and the Îles de Madeleine archipelago. St Pauli Island, located north of Cape Breton, is sometimes called the “Graveyard of the Gulf” because of the number of ships that have wrecked on its rocks.
In 1534, French explorer Jacques Cartier was the first documented European to visit the Gulf of St. Lawrence. Centuries prior to this, the First Nations peoples used the gulf for fishing and transportation. Today, the gulf’s coastline is peppered with protected areas and spectacular national parks. Among them are Cape Breton Highlands National Park, which is home to the popular Cabot Trail, and Prince Edward Island National Park, where walking and cycling trials lead to scenic beaches.
Persian Gulf (Arabian Gulf)
The Persian Gulf (also called the Arabian Gulf) extends from the Indian Ocean and covers an area of 93,000 square miles, between the Arabian Peninsula and the coastlines of Iraq, Iran, and Kuwait. With a 615-mile coastline, the gulf is relatively shallow and rarely plunges deeper than 300 feet. It connects to the Gulf of Oman and the Indian Ocean via the Strait of Hormuz, which is an important gas and oil shipping route. Since World War II, the region has been responsible for most of the world’s oil production. Estimates suggest that two-thirds of proven oil preserves and one-third of proven natural gasses are located here.
Besides the oil industry, the Persian Gulf possesses extensive fishing grounds and bountiful pearl oysters. Historically, it was a region that also thrived on industries such as boat building, camel breeding, date growing, and sailcloth making. The area’s topography is characterized by the long and mountainous Iranian coastline and the sandy beaches of the Arabian shoreline — the latter being home to the futuristic skylines of cities such as Abu Dhabi, Dubai, and Kuwait City. Popular tourist sights in the region include Dubai’s Burj Khalifa skyscraper, Iran’s Nasir al Mulk Mosque, and Bahrain’s massive Al Fateh Grand Mosque.
Gulf of Alaska
Located off the southern coast of Alaska, the 592,000-square-mile Gulf of Alaska extends from the Alexander Archipelago in the east to Kodiak Island in the west. The gulf’s rugged coastline is heavily indented by fjords and sea inlets, including the Cook Inlet and Prince William Sound. Also located along the coastline of this subarctic region are the towering Chugach, Kenai, and St. Elias mountain ranges. Two of Alaska’s biggest glaciers, Bering Glacier and Malaspina Glacier, are found here, too.
The Gulf of Alaska is also home to the state’s largest city, Anchorage. It’s known for industries such as salmon fishing and attracts tourists as a gateway to outdoor adventures in nearby Chugach State Park and Kenai National Wildlife Refuge. Another popular tourist destination is Kodiak Island. At 100 miles long and 60 miles wide, it’s the largest Alaskan island and second-largest island in the United States, after Hawaii’s Big Island. Kodiak Island has a varied topography made up of uplands, forested shorelines, and moist tundra. Over half of the island is covered by the Kodiak National Wildlife Refuge, where it’s possible to spot bears, black-tailed deer, red foxes, and numerous bird species.
Gulf of Guinea
Bordering the western arch of Africa beside the tropical Northern Atlantic Ocean is the Gulf of Guinea. Its coastline touches nine countries, from Liberia in the northwest to Gabon on its southeast. Several rivers flow into the gulf, including the River Niger and Volta River. This river discharge and high rainfall in the region are factors that influence the low salinity of the gulf’s waters. A knock-on effect of the low salinity is minimal marine flora and fauna.
One of the most geologically interesting features of the Gulf of Guinea is the Cameroon line, a volcanic chain that spans both the ocean and the continental crust. From Mount Cameroon, in Mount Cameroon National Park, the chain travels northeast toward Lake Chad and southwest across four tropical islands. The islands are busy tourist destinations known for pristine beaches, varied landscapes, and exotic wildlife. Portuguese-speaking São Tomé and Príncipe offers opportunities to explore jungle preserves, hike to the summit of Pico do São Tomé, and swim in crystalline waters. Closest to the mainland, Bioko is famous for the primates and sea turtles that inhabit Luba Crater Scientific Reserve.
Gulf of Mexico
Extending from the Atlantic Ocean and formed by shifting plate tectonics approximately 300 millions of years ago, the Gulf of Mexico is often called “America’s Sea.” This bountiful body of water — considered the largest gulf in the world — boasts a surface area of 600,000 square miles and is bordered by eastern Mexico; Cuba; and the Gulf Coast states of Florida, Alabama, Mississippi, Louisiana, and Texas. Although largely characterized by shallow intertidal zones, the gulf also has several deeper areas. One of these is Sigsbee Deep, a triangular basin with a maximum depth of 14,383 feet.
Italian merchant Amerigo Vespucci was the first European to navigate the gulf in 1497. Just over half a century later, Spanish explorer Tristan de Luna established a settlement at Pensacola Bay. Before Europeans arrived, Mayan and Incan civilizations used the gulf as an important trade route. With 3,700 miles of coastline dotted with glorious beaches, the Gulf of Mexico is now a hotspot for fishing, watersports, and diving. Among the varied marine life are dolphins, seabirds, sharks, turtles, and whales. The U.S. portion of the gulf shelters several protected seashores and national parks, including Dry Tortugas National Park, Everglades National Park, and Padre Island National Seashore.