Key:defensive_works

defensive_works
Description
Military constructions or buildings designed for the defence of territories in warfare
Group: military
Used on these elements
Documented values: 3
Useful combination
name=* heritage=* wikidata=*
See also
historic=*
Status: approved
defensive_works=* More details at taginfo
Tools for this tag
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This key is used to tag individual defensive structures mainly at historic/pre-modern fortifications. It is intended for all structures that were built for the defence of territories in warfare. This includes fortified settlements as well as forts that are/were uninhabited during peacetime.

Values for defensive_works=* contain terms used in fortification engineering.

How to map

Individual defensive works should be mapped as Nodes at their centre, as Ways along a centre line or as Areas along the outlines. The best fitting method depends on the size and shape of the structure. They should be tagged with defensive_works=* and may receive additional tags.

Mappers are encouraged to combine this tag with other tags where they are relevant. If a structure is actively used by the military, it is recommended to add a military=* tag to it.

Tagging

Key	Value	Description	Sample photo
defensive_works	barbican	A barbican
defensive_works	bastion	A bastion. The tag defensive_works=demi-bastion also has minor usage.
defensive_works	battery	A fixed artillery battery. Individual guns or cannons can be tagged with historic=cannon.
defensive_works	batardeau	A batardeau
defensive_works	caponier	A caponier
defensive_works	cavalier	A cavalier
defensive_works	counterguard	A counterguard
defensive_works	counterscarp	A counterscarp
defensive_works	couvreface	A couvreface
defensive_works	crownwork	A crownwork
defensive_works	curtain_wall	A curtain wall. See also defensive wall.
defensive_works	faussebraye	A faussebraye is a lower wall in front of the main defensive wall of a fortification.
defensive_works	glacis	A glacis is an artificial slope that is part of a fortification.
defensive_works	hornwork	A hornwork
defensive_works	inundation_sluice	A sluice made for military inundation
defensive_works	lunette	A lunette or demi-lune is an outwork in the shape of a half-moon.
defensive_works	moat	A moat that historically provided a fortification with a preliminary line of defence. For moats filled with water, add the tags natural=water and water=moat.
defensive_works	motte	A motte
defensive_works	ravelin	A ravelin
defensive_works	redan	A redan
defensive_works	redoubt	A redoubt
defensive_works	reduit	A reduit
defensive_works	roundel	A roundel
defensive_works	tenaille	A tenaille
defensive_works	water_gate	A water gate
defensive_works	User-defined	Use technical terms in fortification engineering.

Tags to use in combination

• name=* - if a defensive structure is named. Do not use the name of the fortification to tag individual structures.
• heritage=* - if the structure has a heritage status. If only the entire fortification has a heritage status, do not use heritage tags for individual structures.
• building=bunker - if the structure is a bunker
• start_date=* - year of completion
• abandoned=yes - if the structure has been abandoned and shows signs of decay
• ruins=yes - if the structure is in ruins

Similar and related tags

• barrier=city_wall
• barrier=sally_port
• barrier=tank_trap
• bunker_type=*
• historic=cannon
• historic=castle_wall
• historic=city_gate
• historic=citywalls
• historic=fort
• military=trench
• tower:type=defensive
• wall=castle_wall
• water=moat

Diagrams

• 
  Star fort
• 
  Glacis
• 
  Counterguard and couvreface
• 
  A bastion with three cavaliers
• 
  Curtain walls of a bastion fort
• 
  A crownwork (A) and a lunette (B)
• 
  Redan and flèche