The Thirty Base Tour started at Marlins Park and will spend a series at every MLB club's home ballpark. (MLB.com)

Take your base.

It could be worth a fortune someday.

Bidding is underway through Oct. 31 at the MLB.com Auction on three custom bases that are now traveling Major League Baseball in an unprecedented initiative called the Thirty Base Tour. This set will be used over 110 days in all 30 MLB parks and authenticated every step of the way.

These first, second and third bases each also will be used at Target Field for All-Star events including the Sirius XM All-Star Futures Game, the Gillette Home Run Derby and the 85th Midsummer Classic on July 15. All proceeds from the sale of the bases will benefit MLB's Reviving Baseball in Inner Cities (RBI) Program.

The traveling bases began their baseball expedition in Miami in mid-June, and by the end of the regular season, the Thirty Base Tour will have spent an entire series at every MLB club's home ballpark. During each series, all three bases will be used in-game for a minimum of three innings and in the same base position each time.

Bidding starts at $1,000 and can be raised in $25 increments. These already are artifacts that would be Cooperstown-worthy, because they were used last week during Tim Lincecum's no-hitter for the Giants and also in rookie outfielder Gregory Polanco's first five-hit game.

"I had only one superstition," Babe Ruth once said. "I made sure to touch all the bases when I hit a home run."

Maybe some memorabilia collector will touch all of these. Home plate not included.

After being removed from play, an MLB Authenticator officially authenticates the bases and documents their use before they travel to their next destination. Fans can follow the bases online through the MLB Authentication database at MLB.com by their hologram numbers: first base (HZ110358), second base (HZ110359) and third base (HZ110360).

Use the #TravelingBases hashtag to track the progress of this set from park to park and to share your latest bid with other fans. Follow @MLBAuthenticator for more on this subject.

The RBI program, which has served more than 1 million young people since its inception in 1989, is administered by MLB and is designed to give young people from underserved and diverse communities the opportunity to play baseball and softball, while also encouraging academic achievement and success and teaching the value of teamwork and other life lessons. RBI currently serves more than 220,000 young men and women in more than 300 programs in approximately 200 cities worldwide. MLB and its clubs have designated more than $30 million worth of resources to the RBI program, and all 30 clubs support RBI leagues.