Casco Bay

Keep an eye out for birds, seals, and the occasional whale while you hike along the coast, sail through the harbor, or hop on the ferry to visit Casco Bay’s seven accessible islands.

Most bay tours leave from nearby Portland, Maine’s capital city, and sometimes include a city tour along with a coastal sightseeing excursion. You can also opt for a private charter vessel in order to see Casco Bay’s lighthouses and historic forts at your own pace.

• Casco Bay is a must-see for nature and history lovers.

• With relatively calm water conditions and multiple islands to explore, Casco Bay is a great destination for families with kids.

• Remember to bring comfortable shoes and sun protection.

• It’s a good idea to dress in layers, as the weather can change quickly in this coastal region.

• Ferries from Portland to the islands in Casco Bay are accessible to wheelchairs and strollers.

Casco Bay is located just north of Portland, Maine. Ferries operate daily between Portland and the islands of Casco Bay, and private charter vessels travel through the harbor as well.

You can visit Casco Bay year-round, but summer is a lovely time, when the days are usually sunny and warm. Head out onto the water at dusk to see colorful sunsets over the bay.

Don’t miss Peaks Island, which is home to beaches, restaurants, and an art community, while Long Island is known for its hiking trails and conservation areas. Bailey Island is also a good hiking spot, while Diamond Cove (located on Great Diamond Island) is home to Fort McKinley—a structure designed to defend Portland Harbor during the Spanish-American War.

That depends—there’s plenty to consider. Casco Bay in Maine is home to hundreds of islands, which range from small and uninhabited to populous and popular. Some of the best to visit include Peaks Island (the closest to Portland), Great Diamond (home to Fort McKinley), and the scenic Chebeague Island.

There are multiple theories about the origins of Casco Bay’s name. Abenaki native people called the bay “Aucocisco,” which may have been shortened by European visitors. As an alternative theory, some believe it was named by Portuguese explorer Estêvão Gomes in 1525, thanks to its resemblance to a helmet (casco).

Although a popular myth suggests that there are as many islands in Casco Bay as there are days in a year, the bay contains far more. According to current estimates, there are a staggering 785 islands, islets, and exposed ledges scattered across Casco Bay.

Peaks Island—the most populous island in Casco Bay—is also the closest one to Portland. Home to around 1,000 permanent residents (alongside an additional 2,000 residents in summer's high season), the island is 17 minutes by ferry from Maine’s largest city—and it's thought of as Portland's bonus neighborhood.

Boasting unspoiled New England coastal scenery and habitats, Casco Bay is home to a wealth of wildlife, including harbor seals and gray seals, as well as lobster, bluefin tuna, porpoises, and dolphins. The bay is also frequented by migratory whales, including humpback, pilot, finback, and minke whales.

Casco Bay is home to numerous aquatic bird species. Birdwatchers come from far and wide to catch glimpses of the bay’s northern gannets, Manx shearwaters, petrels, sandpipers, terns, cormorants, and more. If you want to embark on a birdwatching excursion, follow the Casco Bay Birding Trail—and keep your eyes peeled.