Las Vegas may have a few more places to test your luck, but here in Alaska, we double-down every spring for the Nenana Ice Classic. All over the state, bright red ticket cans signify the start of the annual betting lottery that awards up to $300,000 to the contestant who correctly guesses the exact date and time the ice will break on the Tanana River.

The event dates back to 1917 during the construction of the Alaska Railroad. Engineers had to halt work for the winter once they reached the frozen solid Tanana River. To keep themselves entertained while sitting around waiting for the river to thaw, they anteed up a total of $800 to wager on the exact time the Tanana River ice would break.

Every year since then, Alaskans throw down $2.50 per ticket containing their guesses of when the spring thawing will loosen the frozen river enough to move a wooden tripod sitting on the ice, downstream. After all these years, the folks over at the Nenana Ice Classic have measuring the ice breakup down to a science. To determine the official time of ice breakup, a cable connects the tripod to a clock on shore. When the tripod moves, the cable tightens, the clock stops and an alarm sounds. (If you’re the lucky winner, the alarms sounds strikingly like the CHING CHING of a cash register.)

Tickets for Alaska’s oldest guessing game went on sale Feb. 1 and will be sold through April 5 when all bets are locked! Click here for a list of locations to buy tickets.

Want some helpful hints? In 2010 the ice broke for the ninth time on April 29^th tying with April 30^th as the most winning date. It was also the seventh time the ice has gone out between 9 and 9:59 a.m. But don’t think betting this year will be easy. When they measured the ice earlier in February, it was the thinnest it’s been since 2006, but it’s not just the thickness of the ice that matters. Wise betters also factor in air temperature, snow cover, wind, water temperature, and depth of water below the ice.

But we recommend testing the conditions yourself, by scheduling a trip to Fairbanks  this month to gage the Interior weather’s progress. Even if it doesn’t result in hitting the jackpot, you’re sure to enjoy some nice pre-spring temperatures.

Last year, three ticket holders out of the 234,000-sold, shared the prize, correctly guessing 9:06 a.m. Alaska Standard Time, April 29. For more information on the Nenana Ice Classic, click here.