Longing to see area in East Germany (5)
I believe the answer is:
eager
'longing to see' is the definition.
(I've seen this before)
'area in east germany' is the wordplay.
'area' becomes 'a' (maths abbreviation).
'in' means one lot of letters goes inside another.
'east' becomes 'e' ('E' can be a synonym of 'east').
'germany' becomes 'ger' (I've seen this in other clues).
'e'+'ger'='eger'
'a' put within 'eger' is 'EAGER'.
(Other definitions for eager that I've seen before include "Desperate" , "Keen - enthusiastic" , "Alert and active type?" , "Showing keen interest" , "Full of enthusiasm" .)