Fort Mervine Ruins: The First American Fort on the Pacific After the United States took control of the Mexican capital of California at Monterey in July 1846, the US Army built its first American fort on the west coast on this hill. Fort Mervine overlooks the harbor, located above what had been an earlier Spanish and Mexican fort called "El Castillo." It was eventually named for Captain William Mervine. Under direction from Commodore Sloat, Captain Mervine led the forces ashore to raise the American flag over the Custom House of Monterey. Construction of the fort began in 1846 under the direction of engineer Lt. Henry Halleck and the supervision of Lt. Edward O. C. Ord. Both men would later go on to become notable Civil War generals as would a young lieutenant who assisted in the fort's construction named William Tecumseh Sherman. The fort was completed in 1847. Fort Mervine was first known as Fort Stockton in honor of the Navy commander of the Pacific Squadron. When the U. S. Army's Third Artillery arrived in 1847, they renamed it "Monterey Redoubt." But the renaming didn't stop. The fort was called Fort Hill, Fort Savannah (for Commodore Sloat's flagship), Fort Halleck, and so on at various times. But Fort Mervine is the name that finally stuck. Fort Mervine consisted of barracks, officer's quarters, a bakery, and other buildings enclosed by a wood palisade atop an earthen mound. It was 650 feet long and 400 feet wide with ravelins - angled, fortified embankments housing artillery pieces - at each corner. Today only the forward ravelin remains, mounted with four 1861 Siege rifles and one 24-pound siege howitzer. The fort closed in 1852 during the Gold Rush, then was reactivated during the Civil War, only to be closed again in 1865. The ruins of Fort Mervine now stand as the ancestor to the present day Presidio of Monterey.