BALTIMORE (WJZ)— Hundreds of rare, perfect-condition baseball cards went up for auction in Baltimore. They sat untouched in an attic for decades. Collectors paid half a million dollars Thursday night for the best cards of the bunch.

Kai Jackson has more on the bidding war.

A group of cousins will split the money. This first round of cars was a nice payday for the Ohio family, and the money hasn’t stopped flowing yet.

One of the biggest finds in sports memorabilia history went up for auction in Baltimore.

Rare baseball cards from the early 1900s were bid on inside the warehouse at Camden Yards.

In the world of collecting, they’re called the black swamp find.

When the live and online biding was over, three lots of cards sold for $565,000.

“Very excited and just blessed that we were all able to share in this big find,” said Karla Hench, whose family owns the cards.

The valuable cards were found in February in the attic of a house in Defiance, Ohio.

Karl Kissner discovered 700 baseball cards tied in a bundle in a cardboard box where they’d been more than 100 years. The cards belonged to his late grandfather.

“This is a grandfather I never knew, and through this house we were able to uncover so many things about my grandfather,” said Mike Walz.

It’s a collection that included the rare and highly prized Honus Wagner card.

Experts estimate the mint condition cards are worth $3 million.

The $565,000 the Ohio family made from the auction of these baseball cars is big money, and there are still more cards to sell.

“The average condition of these cards is 7s, 8s and 9s, which is just unbelievable,” said Chris Ivy, Heritage Auctions.

Heritage Auctions conducted the event. The organization will return to Baltimore soon for an auction of maritime memorabilia.