W
- wagon roads (1)
- wagon sheds (10)
- waiting rooms (1)
- walkways (4)
- walls (16)
- war (Civil War) (30)
- war (Korean War) (3)
- war (Mexican-American War) (3)
- war (Revolutionary War) (7)
- war (Spanish-American war) (1)
- war (War of 1812) (19)
- war (World War I) (72)
- war (World War II) (212)
- warehouses (181)
- war (349)
- washhouses (19)
- waste disposal facilities (1)
- waste disposal (8)
- watch towers (7)
- water pollution (1)
- water power (9)
- water pumps (3)
- water supply (271)
- water tanks (11)
- water towers (26)
- water treatment plants (9)
- waterwheels (2)
- waterworks (9)
- weapons industry (19)
- weather vanes (1)
- weather (3)
- weigh stations (2)
- weirs (3)
- well houses (8)
- wells (21)
- wharves (6)
- wildlife refuge (1)
- wind tunnels (6)
- wind turbines (1)
- windmills (22)
- winds (5)
- women (2)
- wood bridges (11)
- wood structural frames (1)
- wood trestles (1)
- wood truss bridges (5)
- wooden buildings (1088)
- woodsheds (10)
- woodworking (8)
- wool industry (2)
- woolen mills (2)
- work camps (8)
- working class (1)
- Works Progress Administration (9)
- workshops (53)
- world's fairs (1)
- wrought-iron girder bridges (2)
- wrought-iron truss bridges (11)