Defensive fighting position
A defensive fighting position (DFP) is a type of earthwork constructed in a military context, generally large enough to accommodate anything from one soldier to a fire team.
U.S. Marine in a fighting hole outside Beirut during the 1958 Lebanon crisis
The Salpa Line served Finland fighting against the Soviet Union during the Continuation War. Photo taken in Luumäki, Finland, in 2011.
An Indian Wehrmacht volunteer in a Tobruk DFP along the Atlantic Wall, 1944
German VK 3001H prototype turret mounted on "Tobruk" at Omaha Beach, June 1944
Trench warfare is a type of land warfare using occupied lines largely comprising military trenches, in which combatants are well-protected from the enemy's small arms fire and are substantially sheltered from artillery. It became archetypically associated with World War I (1914–1918), when the Race to the Sea rapidly expanded trench use on the Western Front starting in September 1914.
British (upper) and German (lower) frontline trenches, 1916
German soldiers of the 11th Reserve Hussar Regiment fighting from a trench, on the Western Front, 1916
Plan of Ruapekapeka Pā, an elaborate and heavily fortified Ngāpuhi innovation, which James Belich has argued laid the groundwork for or essentially invented modern trench warfare.
Trenches at the Siege of Vicksburg 1863