Las Vegas (often informally abbreviated to "Vegas") is the most populous city in the state of Nevada, United States, the seat of Clark County, and an internationally known vacation, shopping, entertainment, and gambling destination. It was established in 1905 and officially became a city in 1911. It is the largest U.S. city founded in the 20th century.

The name Las Vegas is often applied to the unincorporated areas of Clark County that surround the city, especially the resort areas on and near the Las Vegas Strip. This 4.5 mi (7.2 km) stretch of Las Vegas Boulevard is mostly outside the Las Vegas city limits, in the unincorporated town of Paradise.

The center of gambling in the United States, Las Vegas is marketed as The Entertainment Capital of the World, also commonly known as Sin City or Vice City, due to the popularity of legalized gambling, availability of alcoholic beverages at any time (as is true throughout Nevada), and various forms and degrees of adult entertainment. The city's glamorous image has made it a popular setting for films and television programs.