Blot on the landscape, one visited by tourist? (5)
I believe the answer is:
sight
I believe this is a double definition.
'blot on the landscape' is the first definition.
(sight can mean an eyesore or blot on the landscape)
'one visited by tourist?' is the second definition.
(as in sight-seeing)
(Other definitions for sight that I've seen before include "Could be a jolly" , "Aiming device on gun" , "24" , "a great deal" , "Show" .)