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Cape Cod island with chateau listed for $18.5 million

Buying Luxury Cape Cod
The home sits on a 5.2 acre island.
The home sits on a 5.2 acre island. Amber Jane Barricman of Amber Jane Photography

Living on St. Mary’s Island in Osterville does not require a boat or stocking up on food from the mainland for weeks at a time. This 5.2-acre island is barely separated from Cape Cod; you can drive right home to it via causeway — if you have $18,500,000, that is.

The eight-bedroom, 7.5-bath, 8,931-square-foot main residence on the island, 251 Seapuit Road, was built in 1920 in a style reminiscent of the chateaus in Normandy, France. The home features stucco and stone walls, steeply pitched gables, and terra-cotta windows. Walk through the arched portico and into the entrance hall, which is clad in oak paneling and has an ornate carved staircase.

On the first floor, there is a two-story library with a fireplace and a staircase leading to a turreted bedroom suite; a study (connected to the library via a secret passage) with a bay window overlooking the water; a mudroom; butler’s pantry; a half bath; and a formal living room with floor-to-ceiling windows, a fireplace with a 17th-century mantel, and French doors to an English-stone terrace. This floor also offers a dining room that leads into an eat-in kitchen featuring high-end appliances, a beamed ceiling, and a large center island.

The second floor is where the master is located. It offers a bath, walk-in closet, dressing room, and kitchenette. Two other bedrooms with en-suite baths, hardwood floors, and fireplaces are also located on this floor.

There are also two guest suites attached to the house, one of which has a full kitchen and living and family rooms. A third guest suite — with a bedroom, living room, and bath — is accessed by private staircase.

If that isn’t enough room for your guests, there is also a carriage house, which offers a full kitchen, living room, bath, sleeping areas, and an attached three-car garage.

The grounds are lush and include panoramic water views, along with a private deep-water dock.

Check out more photos of the island:

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