Inn at Diamond Cove

The Inn at Diamond Cove was an 1891 U.S. Army fort before it was a hotel. Forty-four rooms inside the converted barracks of Fort McKinley, on Great Diamond Island in Casco Bay, fifteen minutes by ferry from Portland's downtown waterfront. It's an unusual property by any standard — a fort renovation, an island setting, and a working hotel inside a small year-round island community.

The fort itself was decommissioned in 1950 and sat largely empty for decades before the conversion. The renovation kept the brick barracks structures and added the necessary modern infrastructure underneath. The result is a property that looks like a small New England village because it once was one.

The setting

Great Diamond Island is one of the Calendar Islands in Casco Bay, a fifteen-minute Casco Bay Lines ferry from the Portland waterfront. Once on the island, the only vehicles are golf carts; you walk or ride. The Diamond Cove side of the island has the converted fort, a marina, restaurants, and the inn. The far side of the island is residential and quiet.

The Portland skyline is visible across the water from much of the property. The drive in for most guests is to Portland, then ferry — your car stays on the mainland.

The building

Brick officers' quarters and barracks from the 1890s, restored as the inn's room buildings. White-trimmed wood porches wrap around several buildings; the architecture reads as late-19th-century military rather than resort. Lawns and gravel paths connect the buildings. Public spaces include a small main lobby, a sitting room with a fireplace, and the original parade ground.

It's a country-estate read of military architecture — clapboard porches, formal landscaping, the kind of property where the buildings are part of a planned ensemble.

The rooms

Forty-four rooms across the converted barracks buildings. Categories range from one-bedroom rooms (around $445 in season) up through two- and three-bedroom suites with full kitchens and harbor or lawn views. Beds are queens and kings, linens are good, bathrooms are updated. Many units have full kitchens and living rooms — they're closer to small apartments than conventional hotel rooms, useful for a family or a multi-night stay.

The harbor-view rooms are the ones to ask for; lawn-side rooms are quieter.

Food & drink

Diamond's Edge restaurant is on the property, open to inn guests, residents, and ferry-arriving non-guests in season. The menu is contemporary New England with a heavy emphasis on Casco Bay seafood — oysters from local farms, day-boat fish, lobster done several ways. The bar runs a serious cocktail list and is often the busiest part of the property on summer evenings.

On the property

The fort grounds are the amenity.

• Heated outdoor pool (seasonal)
• Two tennis courts
• Walking trails around the island's interior
• Beach access along the cove
• On-site restaurant and bar
• Open year-round (though the island operates at a quieter cadence in winter)

Who it's for

• Couples and families who want an island stay accessible by short ferry rather than a long boat
• Travelers using Portland as a long weekend who want a night out on the water
• Anyone interested in 19th-century military architecture (Fort McKinley is unusual)
• Multi-generational groups — the suites with multiple bedrooms are well-suited

Who it's not for

• Travelers who want a downtown-Portland walking-distance base
• Anyone who needs a 24-hour hotel operation; the island operates at island pace
• Light packers — you'll be moving luggage on and off a ferry

Nearby

Portland's Old Port — the brick warehouses, working waterfront, the restaurant strip on Wharf Street — is fifteen minutes by ferry, with regular service throughout the day. From the Portland end, drive south for Cape Elizabeth and Portland Head Light; drive north for L.L. Bean's flagship in Freeport. On the island itself, the residential side has walking trails through woods and along the shore. Casco Bay's other islands — Peaks, Long Island, Cliff — are reachable on the same ferry network for day trips.