|natural = bay|
|An area of water mostly surrounded by land but with level connection to the ocean or a lake.|
|Used on these elements|
|Tools for this tag|
A bay is an area of water mostly surrounded or otherwise demarcated by land but with a level connection to the ocean or to a larger waterbody. Bays often have calmer waters than the surrounding sea, due to the surrounding land blocking some waves and often reducing winds. Bays can also exist within a lake or pond.
A large bay may be called a gulf, a sea, a sound (or sund), bight, or a bay=fjord (if created by glacial erosion, see on Wikipedia). A cove is a circular or oval coastal inlet with a narrow entrance; some coves may be referred to as bays.
How to map
Bays can either be mapped as nodes or as areas. When you map a bay as a node the node should be placed approximately at the middle of the bay with equal distance to the coast enclosing the bay on all sides. When mapping bays as an area the following things are important:
- Since the edge of a bay towards open water is often not well defined mapping bays with a large opening can be problematic with regards to Verifiability.
- The edge of a bay towards land should coincide with the coastline. You should never close the coastline at the outer side of a bay as it is part of the ocean (or the lake) it is connected to.
- When mapping large bays as areas the resulting multipolygon relations will often be extremely large and complex so mapping with nodes, like for place=ocean, could be preferable. Some mappers also prefer to use approximate or simplified polygons instead of the coastline although such mapping is geometrically not verifiable and can be difficult to maintain because of the additional geometries.
- There is currently no definitive rule if small islands within a bay should be mapped as part of the bay or if they should be excluded of the bay area as inner rings of the corresponding multipolygon relation.
Rendering in OpenStreetMap Carto