A seawall is a coastal defense structure, a structure to protect against flooding and erosion, built along the coast.  May be as simple as large rocks and debris lining the coastline or it may be an actual wall built along the coast line.  In Japan [[tetrapod]]s are commonly used for seawalls.

h4. See also

* [[Breakwater]]
* "Wikipedia: Seawall":[https://en.wikipedia.org/wiki/Seawall]
seawall