In casual footwear, the Queen goes to north land (7)
I believe the answer is:
terrain
'land' is the definition.
(terrain is land or territory)
'in casual footwear the queen goes to north' is the wordplay.
'in' means one lot of letters goes inside another.
'casual footwear' becomes 'terai' (I can't explain this - if you can you should give a lot more credence to this answer).
'the queen' becomes 'r' (abbreviation for regina, e.g. in ER ).
'goes to' says to put letters next to each other.
'north' becomes 'N' (abbreviation).
'terai' going around 'r' is 'terrai'.
'terrai'+'n'='TERRAIN'
Can you help me to learn more?
(Other definitions for terrain that I've seen before include "Piece of ground" , "Stretch of land, emphasising natural features" , "Physical feature of a stretch of ground" , "Type of countryside" , "Land (as base for action)" .)