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 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
• 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