Taking turns, watch in raft, an all-round vast place (6)
I believe the answer is:
africa
'vast place' is the definition.
'taking turns watch in raft an all-round' is the wordplay.
'taking turns' indicates alternate letters (back).
'an' becomes 'a'.
'all-round' is a reversal indicator.
'watch'+'in'+'raft'='watchinraft'
The alternating letters of 'watchinraft' are 'acirf'.
'acirf'+'a'='acirfa'
'acirfa' backwards is 'AFRICA'.
(Other definitions for africa that I've seen before include "Large land mass" , "The CIA and RAF are found on the continent" , "Burn; fish" , "Mali's continent" , "Continent S. of Europe" .)