Where's There: Cemetery Island
The "remote rock" is about an hour's ride by boat from Vinalhaven, where Johnny Dixon and Father Higgins are stationed in an attempt to locate the missing Professor Childermass.
The island appears to be inhabited mostly by rocks – "Johnny kept tripping over them"  – and pine trees, whose "dead pine needles"  and pine cones were probably strewn around the island from the area’s high winds. The only building is a chapel, "a tiny brick church with quatrefoil decorations on the front and a pointed door with a cross over it"  that sits atop a hillside. At the bottom of the hill is the cemetery from which the island is named with "long rows of pale white slabs"  surrounded by a "low fieldstone wall" . The entrance to the cemetery is guarded by a noisy "rusting iron turnstile" . Professor Childermass is eventually found on, and rescued from, the island.
While there are plenty of small islands off the coast of Maine that could easily fit the description of Cemetery Island, the inspiration for the island’s name may have come from Isle Royale National Park, near Houghton, Michigan. Seeing how this is in Bellairs' native Michigan, it is quite possible that Bellairs probably either visited the park or read about it at one point and later recalled the sinister-sounding name for his book.
The tiny island, about one-and-a-half acres, is heavily wooded with a handful of marked graves in the center. Three of the graves are dated (1851, 1853, and 1854) and are possibly related to the mining effort on the island at that time. There is a popular story that some of the graves are from victims of the Algoma passenger ship that wrecked in 1885 or the victims of a fight between Cornish and Irish miners. According to the staff of Isle Royale National Park, there isn't much evidence to substantiate those stories but they are popular and so they remain. Remnants of an old log cabin have also been identified on the island but it is not known whether it dates from the 1850s mining period or later.
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