East Coast, East coast, or east coast? [duplicate]

Is it East Coast, East coast, or east coast when used in a sentence such as, "The airline flies to both the East Coast and the West Coast?" I've seen it all ways. I can't find a definitive answer as to if or where capital letters are needed in this phrase. Thanks for your help.

It depends on whether you're using it as the name of an area of a description of an area. When it's used as a name, you capitalize it:

• I'm going to the East Coast this summer.
• There are lots of farms in the Midwest.

When you're using it as a general description of a place, it's not capitalized:

• The east coast of the U.S. is a popular destination for tourists.
• Illinois is a midwestern state.