Thousands of poker players from around the world make an annual pilgrimage to Vegas for the Main Event, with the ultimate winner walking away with well more than $5 million in cash for his or her victory.

The unofficial world championship of poker, the Main Event draws the biggest field of any live poker tournament each year, with attendance in 2010 of 7,319 players.

The field is so large every year that the WSOP schedules four different starting days for players to choose from, with the poker tournament rooms at the Rio filled to capacity each starting day.

The Main Event comes at the end of a nearly 60 tournament-series that began in late May in 2011, with many poker players pinning all their hopes on a good showing in the Main Event to make up for a typical summer of chasing an elusive big payday in WSOP events.

Winners of most preliminary events collect over $300,000, with a few paying the winner over $1 million.

Due to the US government's crackdown in April on online casino and poker sites, it's a pretty safe bet that attendance for the 2011 Main Event will likely be lower than in 2010.

But a good turnout for preliminary WSOP events has many in the poker industry crossing their fingers that the drop-off won't be that dramatic.

The WSOP Main Event is a popular draw for tourists and spectators as well, with many taking a break from slot machines to come watch some of the world's most famous poker pros in action live and in person at the tables.

Hundreds of amateur players also qualify to play every year through satellite tournaments and promotions on major online casino sites including 888.com, Party Casino and William Hill Casino.

The Main Event is also unique in that the field plays down to 9 players by July 19th, but then takes a break until November when the final nine players (dubbed the "November Nine") return to the Rio to battle it out and crown a winner.