Isle au Haut, Maine. Built in 1907, the Keeper's House is on the National Register of Historic Places, homes officially deemed worthy of preservation. The four-bedroom, solar-powered house has ornate molding, wood floors, and wood stoves.

The property, on Penobscot Bay, has 700 feet of waterfront, two cottages, a two-bedroom guesthouse, a boathouse, and a deep-water dock. The town maintains the lighthouse. $1,975,000. The Knowles Company, (207) 276-3322.

Woodinville, Washington. The Nelson-Parker house was built in the late 19th century by Nordic settlers. The four-bedroom, Swedish-influenced log home was constructed from hand-felled red cedar and features three fireplaces, cathedral ceilings, an art studio and wine-making station in the cellar, and a wraparound deck.

The 3.6-acre property has panoramic views and includes a vegetable garden and a barn. $2,500,000. ­Cindy Kelly, Compass, (425) 260-2017.

Sarasota, Florida. Architect Thomas Reed Martin designed this three-bedroom ­Mediterranean ­Revival in 1927 for Detective William J. Burns, called the American Sherlock Holmes.

Details include a marble fireplace, the gift of circus master John Ringling; the original iron staircase; a sunroom with French doors; and a master suite with bay views. Outside are a large pool, a dock, and a 7-ton boat lift. $3,650,000. Lynne Koy, Coldwell Banker Residential Real Estate, (941) 544-5117.

Portland, Oregon. This five-bedroom home was built by architect ­Richard Sundeleaf in 1940. Remodeled in 2017, the house has a gourmet kitchen with marble counters and a living room with a dining area that leads to a covered porch.

The 1.1-acre property has a sports court and mature trees; the brick patio features a stone wall with a built-in fireplace. $1,935,000. Suzann ­Baricevic Murphy, (w)here, (503) 789-1033.

Newport, Kentucky. Originally a wood church built in 1901, this four-bedroom home stands in the East Row Historic District. The open living space has 44-foot ceilings, a kitchen built into the nave, and a master suite in the choir loft.

Recent improvements include a new heating system, exterior paint, and a two-car garage. $625,000. Adam Sanregret, Coldwell Banker West Shell, (513) 321-9944.

Middletown, Connecticut. The Captain Giles Wilcox House, a four-bedroom Georgian Colonial, dates to 1786. The home features the original hardware, paneling, and wainscoting; six fireplaces; and a tavern room, and has been owned by only two families in the past 230 years.

The 3-acre property includes a gunite saltwater pool, a barn, and a manicured lawn. $389,000. Laurie McCann, William Pitt/Sotheby's International Realty, (508) 237-5700.