<Table> <Tr> <Th_colspan="2"> Battle of South Mountain (Battle of Boonsboro Gap) </Th> </Tr> <Tr> <Td_colspan="2"> Part of the American Civil War </Td> </Tr> <Tr> <Td_colspan="2"> The American Soldier, 1862, by H. Charles McBarron, showing U.S. soldiers attacking the Confederates at Turner's Gap in 1862 </Td> </Tr> <Tr> <Td_colspan="2"> <Table> <Tr> <Th> Date </Th> <Td> September 14, 1862 </Td> </Tr> <Tr> <Th> Location </Th> <Td> Frederick County and Washington County, near Boonsboro, Maryland 39 ° 29 ′ 06" N 77 ° 37 ′ 18" W ﻿ / ﻿ 39.48501 ° N 77.62161 ° W ﻿ / 39.48501; - 77.62161 Coordinates: 39 ° 29 ′ 06" N 77 ° 37 ′ 18" W ﻿ / ﻿ 39.48501 ° N 77.62161 ° W ﻿ / 39.48501; - 77.62161 </Td> </Tr> <Tr> <Th> Result </Th> <Td> Union victory </Td> </Tr> </Table> </Td> </Tr> <Tr> <Th_colspan="2"> Belligerents </Th> </Tr> <Tr> <Td> United States (Union) </Td> <Td> CSA (Confederacy) </Td> </Tr> <Tr> <Th_colspan="2"> Commanders and leaders </Th> </Tr> <Tr> <Td> George B. McClellan Ambrose Burnside William B. Franklin Lucius Fairchild </Td> <Td> Robert E. Lee D.H. Hill </Td> </Tr> <Tr> <Th_colspan="2"> Strength </Th> </Tr> <Tr> <Td> 28,000 </Td> <Td> 18,000 </Td> </Tr> <Tr> <Th_colspan="2"> Casualties and losses </Th> </Tr> <Tr> <Td> 2,325 total (443 killed, 1,807 wounded, 75 missing) </Td> <Td> 2,685 total (325 killed, 1560 wounded, 800 missing) </Td> </Tr> </Table> <Tr> <Th_colspan="2"> Battle of South Mountain (Battle of Boonsboro Gap) </Th> </Tr>

Where did the battle of south mountain take place