The shingle-laden St. Stephen's United Methodist Church, above, was built in 1897 on a small island, known as Marble Hill, that only existed for about two decades. How did this island come to be and then not to be? That is the question. And here is the answer:
(Warning: the geography discussed here can get very confusing. These maps will make things much clearer.)
Marble Hill began its life (within the bounds of modern geological history, anyway) as the northernmost part of the island of Manhattan, separated from the Bronx by Spuyten Duyvil Creek, a narrow, meandering waterway connecting the Harlem and Hudson Rivers.
The Harlem River was being developed as a viable commercial waterway in the late 1800s, but Spuyten Duyvil Creek was too shallow and tortuous for large ships to navigate. In 1895, the Harlem River Ship Canal was opened, providing an alternative route to the Hudson, one sufficiently deep and straight for commercial vessels to ply. The canal passed just south of Marble Hill, severing it from the rest of Manhattan and turning it into an island of its own.
It sat alone, encircled by water, for almost 20 years, until 1914, when Spuyten Duyvil Creek was filled in. Politically part of the borough of Manhattan, Marble Hill was now physically connected to the Bronx (although its isolation from the surrounding streets, revealing the old course of Spuyten Duyvil Creek, can still be seen today). This set off some strange territorial disputes, climaxing in 1939 when the Bronx borough president, James J. Lyons, "annexed" the neighborhood, staking a Bronx flag in a promontory overlooking the canal and declaring Marble Hill the Bronx "Sudetenland" (a strange choice of words, as this would seem to make him the Bronx Hitler). But his theatrics were to no avail: Manhattan has never relinquished possession of its little exclave.
Political boundaries and electoral districts aside, however, Marble Hill is practically part of the Bronx today. It has a Bronx zip code and area code, and it belongs to school and community boards in, and receives most of its emergency services from, the Bronx. Geography triumphs over politics, at least in the everyday lives of its residents.