Group touring first city (4)
I believe the answer is:
trio
'group' is the definition.
(a group of three)
'touring first city' is the wordplay.
'touring first' becomes 't' (1st letter of 'touring').
'city' becomes 'rio' (Rio de Janeiro).
't'+'rio'='TRIO'
(Other definitions for trio that I've seen before include "Group of three (musicians)" , "Beethoven's 'Archduke', for example" , "Threesome" , "Three of a kind" , "Beethoven's 'Archduke': famous piece written for this ensemble" .)