Travelled to see old show (5)
I believe the answer is:
rodeo
'show' is the definition.
(rodeo is a kind of show)
'travelled to see old' is the wordplay.
'travelled' becomes 'rode' (eg travelled on a horse).
'to see old' becomes 'o' (common abbreviation eg in OE for Old English).
'rode'+'o'='RODEO'
(Other definitions for rodeo that I've seen before include "display of cowboy skill" , "Wild West show" , "A bunch of cowboys, showing" , "off, sometimes" , "stock venue?" .)