The elegant spa town of Baden-Baden first became a playground for Europe’s royalty and aristocracy 150 years ago. This heritage is reflected in its casino, which is one of the most lavishly outfitted on this list. Inspired by the baroque flourishes of the Palace of Versailles, it boasts red-and-gold poker rooms and a plethora of blackjack and roulette tables.

While musical shows, shopping centers, hotels and elaborate themes help attract visitors to casinos, the billions in profits raked in each year come from games of chance. Slot machines, blackjack, roulette, craps and baccarat provide the gambling that drives the industry.

Security is a major concern for most casinos, especially since gambling involves large amounts of money. On the floor, casino employees keep a close eye on patrons, watching for blatant cheating like palming or marking cards and dice. Table managers and pit bosses also watch over table games with a wider view, looking for betting patterns that might indicate cheating. Each person on a game has a higher-up to whom they report, and every player has a regular manager who tracks their play.

Some casinos offer comps, free goods and services given to “good” players. In exchange for a certain amount of play, gamblers can receive food, drinks, hotel rooms, tickets to shows and even limo service or airline tickets. Ask a casino employee how to get your play rated and see what you’re eligible for. For example, a high roller in the casino might be offered a suite of rooms, meals and other amenities while a low player might only qualify for a few hours at a casino table.