A coastal plain is what you call a plain that lies along a seacoast.
A landlocked country is one that does not have a coastline.
El Salvador..
It is important to have a seacoast because where are the oil companies going get the oil .Not in lakes, ponds, and rivers and these bodies are water are not deep enough to drill for oil . If a country has no seacoast ,it can not give oil to other countries and if a economy is in oil .It will bring no money for the countries and the economy will fail .
Paraguay and Bolivia has no outlet to the sea.
Laos is the only landlocked country in Asia. It has no seacoast, being inland from Vietnam.
seacoast eagle
SeaCoast Airlines was created in 2002.
Seacoast Church was created in 1988.
Seacoast Mavericks was created in 2010.
Seacoast United was created in 2010.
Uruguay, South America is noted for it tourists resorts on the Alantic Seacoast.