EAGLE ISLAND — One of Maine’s lesser-known state parks is the island home of Admiral Robert Peary, who in 1909, with five men and sled dogs, is credited with an expedition to the North Pole.

Eagle Island, a National Historic Landmark, “is a place that Peary and his family called their promised land,” reads a National Park Service plaque on the island. The National Park Service says the island “possesses national significance commemorating the history of the United States” and calls Peary America’s foremost arctic explorer.

Nine nautical miles from South Freeport — two miles from Harpswell — Eagle Island is only accessible by boat. Private companies offer regular transportation to the island — a roughly 45-minute trip that offers the smells and sounds of the ocean air, playful seals, and views of many Casco Bay islands. Once there, Eagle Island presents history, panoramic views and the unique summer Peary home.

Peary, who lived from 1856 to 1920, had his home’s exterior built to resemble a ship; the front lawn is edged stone that is shaped like the bow of a ship, and it faces north, symbolic of Peary’s arctic explorations.

This year the home, which also serves as a museum, is closed due to mold, but the boat ride to the island, the history of Peary and the island, and the building and grounds are still worth the trip. (State officials are assessing the time it will take to address the mold problem and reopen the home.)

Because the island is also a state nesting sanctuary with all kinds of shore birds, Eagle Island trails will be opened in mid-July when the birds end their nesting season.

We set out from South Freeport harbor with Captain Peter Milholland and deck mate Laura Vitali of Seacoast Tours. Milholland’s boat, the Pamela B, is named for his late mother.

Getting to the island from South Freeport takes 45 minutes. On the way Milholland and Vitali shared local history and characteristics, including details on Casco Castle and winter motorcycle races on the frozen bay.

When the boat reached Upper Green Island — home to seals and protected shore birds — Milholland slowed the Pamela B and pointed to an osprey nest. “They’re rebuilding,” he said as the bird rested in the nest. (Binoculars were available onboard). Dozens of harbor seals played in the water or sunned on the rocks.

“At low tide there’s a sandbar,” Milholland said. “Sometimes the seals are stacked up on top of each other. It’s great to see.”

Other times the seals will disappear in the water if a boat gets too close, Vitali added.

Local folklore has dubbed the Casco Bay islands “calendar islands.” They’re so plentiful there’s one for each day of the year, Vitali said, but the islands number far more than 365.

We resumed, and before long Eagle Island was visible.

As the boat reached the island, the Pamela B was greeted by Park Ranger Chloe Kilborn, who helped secure the boat to the moorings.

“The museum isn’t open because of mold (and) the trails don’t open until mid-July because shorebirds are nesting all over the trails and aren’t happy to see humans,” Kilborn said. “But there’s a lovely beach. You’re welcome to walk around the house and look in the windows.”

Former “North Woods Law” star and now park manager Tim Spahr gave a brief talk about the house and Peary.

Peary bought the island for $200 while an engineering student at Bowdoin College in 1881. “Back then it wasn’t prime real estate,” Spahr said.

Born in Pennsylvania, Peary moved to the Portland area as a boy and loved the island, Spahr said. “The architecture of the house reflects a ship and faces north, symbolic of his passion for arctic exploration.”

As Spahr spoke the smell of the sea filled the air, seagulls flew nearby, squawking loudly. A former Coast Guard member, Spahr said walkways on either side of the house and the front deck “remind me of the bridge and wings of a ship.” A lawn elevated in two sections is like a lower and high deck, a flagpole graces the middle of the lawn.

“Peary liked the idea that when on the porch he could not see the ground” and only saw water. “It really felt like a ship,” said Kilborn. The house and the furnishings reflect the Peary family lifestyle in the early 1900s. In the areas of the house that are visible through the windows can be seen ample hints of geography, historic maps, photos and books.

“You can tell how important the study of geography was to not just the admiral but to his children and the family,” Spahr said.

The house has an enclosed porch and a living room with a beautiful three-sided fireplace built with stones from the island. There’s a kitchen and dining area. Upstairs are five bedrooms. Some of the windows on the house resemble portholes and, if inside, would only offer views the ocean, again as if on a ship.

Spahr said Peary’s journey to the frozen north was a product of his desire to explore an area never explored and his background as an engineer and surveyor.

He relied on a crew of four Inuit skilled explorers for survival and moving across the territory with sled dogs. The sled dogs were Inuit dogs from Greenland.

When Peary was on Eagle Island “he used to keep his dogs on that island over there,” Spahr said pointing to a nearby land mass. “See that bullhorn?” he said, pointing to an antique bullhorn in the house. “He used to call his dogs with that,” he said, without further explanation.

After an hour or two walking around the island, it was time to get back on the Pamela B.

Milholland said Eagle Island is “a lesser-known state park mostly because it’s water-access only.” Eagle Island, which is technically a state historic site, offers gorgeous ocean views with no crowds, and a rich history.

There’s a Peary connection with Bowdoin College and its Peary-MacMillan Arctic Museum, Milholland said. “So people can get background there and come out here and see it.”

On our tour of the island in June, John and Deborah Stokes of Colorado made Eagle Island part of their first visit to Maine.

They were all smiles about the experience.

“It’s absolutely beautiful,” he said. “Interesting history, natural history. I thoroughly enjoyed my visit here.”

His wife agreed, sharing her take-away of the tour: “Maine is beautiful.”