The exterior of Flamingo hotel -casino at Las Vegas Blvd., South, in Las Vegas is shown on Tuesday, Oct. 29, (Bill Hughes/Las. The Flamingo Hotel in Las Vegas was one of the earliest luxury resort hotels built in the gaming city. The hotel's mastermind, Benjamin Siegel, has become. The Flamingo Hotel was the third gambling establishment to open on the now iconic Las Vegas Strip and is the Strip's oldest resort. It was the brainchild of.