During the summer of 1925, while he was finishing The Book of Gallant Vagabonds, Beston was also drawing up the plans for his new dune shack in Eastham and had engaged a local carpenter, Harvey Moore, to build it. In early September, Beston took a short trip to Maine to visit Mary Cabot Wheelwright in Castine and the Days in Damariscotta but he soon returned to the Cape, eager to see how construction on the new cottage, which he had dubbed “the Fo’castle,” was progressing. Before the summer was over, construction of the dune shack was completed and Beston spent the next several weeks there, reveling in the beauty of the great beach. Perched atop the dunes, the small house was a trim twenty by sixteen foot structure with a small “piazza,” as Beston called it, facing east and overlooking the ocean. There was but one door, leading from the porch to the main room of the house. As he described the Fo’castle in The Outermost House: "It consisted of two rooms, a bedroom and a kitchen-living room…a brick fireplace with its back to the wall between rooms heated the larger space and took the chill off the bedroom, and I used a two-burner oil stove when cooking. My neighbor built well. The house, even as I hoped, proved compact and strong, and it was easy to run and easy to heat…In my larger room, I had a chest of drawers painted an honest carriage blue, a table, a wall bookcase, a couch, two chairs, and a rocker. My kitchen, built yacht fashion all in a line, stood at my southern wall. First came a dish and crockery cupboard, then a space for the oil stove—I kept this boxed in when not in use—then a shelf, a porcelain sink, and the corner pump. Blessed pump! It never failed me or indulged in nerves."
The water quality on the beach varied greatly, so Beston was delighted to chance upon a well of fresh water as good as he could possibly have hoped. In what he called his “somewhat amateur enthusiasm for windows,” Beston installed ten of them, seven in the main room and three in the bedroom. He soon found that the glare of sunlight, sand, and sea was often overpowering and he was forced to close the shutters originally intended for winter service. While he never mentions the sanitary facilities of the Fo’castle, that rustic staple, the outhouse, was located a short distance from the dune shack.
The solidity of the house’s construction was soon put to the test when a powerful autumn gale hit the Cape. The afternoon before the night of the gale, the winds and rain suddenly picked up as the storm hurtled out of the northwest. “All the afternoon before the night of the gale,” Beston wrote, “a raw, rainy, wild afternoon, the fo’castle was the Hotel Astor of the dunes for I had a succession of frozen gunners, clammers, Eastham high school boys, eel-pot setters and quahaugers come in to get warm. It was ever so interesting and picturesque. I gave ‘em all a cup of hot tea and milk and a blessing. Then came swift night and the rising hullaballo.” The storm intensified that night, but the Fo’castle passed its first great test with flying colors: "The little house stood solid as a rock, but it thrummed in the fearful wind just the way a church window does when an organist steps on the gas. Outside, in a dark of chaos, the whole beach was on the move; sand, pebbles, wave spume, old wreckage, driftwood and seaweed all hurtling south through the pitch black night at 80 miles an hour. I went out to see if my house was still ashore and as I went around the corner, a skunk as large as an ant-eater went past me apparently a good three feet from the ground and dissappeared (sic) in the direction of Martha’s Vineyard. I stood watch the whole night, wondering just when I would come to and say “Ain’t Portugal Pretty?” but the blessed fo’castle stood like a tower and the exhausted dawn found us still anchored to the sands."
Beston declared his first stay at the Fo’castle to be “about the best two months I’ve ever had.” Still, he had not yet determined that he would write a book about the Cape; that would come the following year.