The John Innes Kane Cottage, also known as Breakwater and Atlantique, is a historic summer estate house at 45 Hancock Street in Bar Harbor, Maine. Built in 1903-04 for John Innes Kane, a wealthy grandson of John Jacob Astor and designed by local architect Fred L. Savage, it is one of a small number of estate houses to escape Bar Harbor's devastating 1947 fire. An imposing example of Tudor Revival architecture, it was listed on the National Register of Historic Places in 1992.