(CNN)The online review site Yelp isn't just a place to compare local dry cleaners or find out if anyone, ever, has patronized the shady, constantly shuttered takeaway joint on your corner.
It's also a handy tool for the international tourist, with users leaving feedback on everything from the quality of the eggs at Las Vegas casino breakfast buffets to the lines at Paris's Musee du Louvre.
Yelp's users are, primarily, an enthusiastic and appreciative bunch.
"Michelangelo, you really outdid yourself," user Kathryn W. of Long Island notes approvingly of the Sistine Chapel, in a characteristically positive review.
But for a small but vocal minority of Yelp's unhappiest travelers, the world is full of disappointing discoveries.