CRYPTIC COLOSSUS 172

Check that T in the 7th place. An I maybe? The answer is staring you in the face. Look at the clue. It's got all the standard cryptic clue hints.

Oh what the hell

COunty AS middle of ScoTLand IN Eastern edge of sea and land

CO is short for county, e.g. Co. (County) Durham in England, and the Irish counties are referred to that way.
AS is there for you to see
TL is in the middle of the word "Scotland"
IN is there for you to see
E is short for East.

A coastline is the edge of the sea (and the land).

Many thanks. Should have used both my heads