These are irritating for sightseers naturally (8)
I believe the answer is:
eyesores
I'm afraid I can't explain this answer.
Can you help me to learn more?
(Other definitions for eyesores that I've seen before include "They're very ugly to the eye" , "ugly looking things" , "Carbuncles" , "They are offensive to see" , "Things that are ugly to look at, hurt optics" .)