Founded in 1966 by Jay Sarno and Stanley Mallin, Caesars Palace established a kind of playful elegance other properties would soon emulate, and, remarkably, which it maintains to this day. A great deal of Vegas’ history—boxing matches, daredevil stunts, legendary musical residencies—was written within these Roman walls. 702-731-7110, caesars.com/caesars-palace.

Runner-up: Flamingo