Paris' centuries-old Louvre Museum — home of da Vinci's iconic Mona Lisa — is getting an $800 million makeover, and American visitors will have to help pay for it.

Already, the museum has capped daily attendance at 30,000 people, who mostly enter via the Louvre Pyramid, a glass-and-steel structure designed by the architect I.M. Pei in the 1980s, during the ...