Terribly pleased about a new walkway (9)
I believe the answer is:
esplanade
'walkway' is the definition.
(esplanade is a kind of walkway)
'terribly pleased about a new' is the wordplay.
'terribly' is an anagram indicator.
'about' indicates putting letters inside.
'a new' becomes 'an' (I've seen this in other clues).
'pleased' with letters rearranged gives 'esplade'.
'esplade' placed around 'an' is 'ESPLANADE'.
(Other definitions for esplanade that I've seen before include "Long level area for walking beside the sea" , "Walkway by the sea" , "A leap ends (anag) - seaside feature" , "Seafront walk" , "Seaside road" .)