The Mona Lisa, Louvre, Paris

The Mona Lisa is the world’s most disappointing selfie spot: 10 million annual visitors crowd elbow-to-elbow for an average 15-second glimpse of a 77 cm x 53 cm painting—smaller than most laptop screens—encased in bulletproof glass. In peak summer months, the wait in the Salle des États can exceed 90 minutes, making it the most time-inefficient attraction on this list. Compared to the 2.6 million visitors at #2 Angkor Wat, the Louvre’s density is six times higher per square meter, and the viewing time per visitor is 80% shorter than the typical cultural site benchmark, which averages 1.5 minutes.