Most of Harlem was built up in the 1880s through 1910 so finding anything that existed prior to these decades can be difficult. Alexander Hamilton's house named Hamilton Grange which is located on the north side of St. Nicholas Park at 141st Street was built in 1802 and is by far the oldest structure in Harlem proper. In second place from what we can see is another clapboard house that is located in Manhattanville at West 126th Street that belongs to St. Mary's church. This parish building was built back in 1851 and both structures are an example of a time when Harlem was all about country living. It is rather odd that nothing else really remains from the late 1700s or early 1800s in Harlem so these buildings are particularly extraordinary in themselves.