sentences:  The original (lower) Craighill Channel was marked with range lights in 1875, following two years of temporary lightships; the cutoff was marked with the upper range lights in 1886, replacing the North Point range, which had been discontinued in 1873.In later years a pair of skeleton towers were erected on Locust Point to mark the Fort McHenry Channel, the final leg from the end of the Brewerton Channel to Curtis Point and the Inner Harbor.All of these lights remain in use, though of course all have been automated.