Fodor’s travel guides are being sold by Penguin Random House to Internet Brands, which is backed by investment firm KKR.

A major reason for the sale appears to be to jump-start the digital side of the operations. The guides, started by worldwide traveler Eugene Fodor, have been around for 80 years.

When the company was acquired 30 years ago by Random House, Fodor’s was the reigning king of the travel book world. It is still the largest print travel guide, but newer, digital travel sites had left fodors.com in the dust in recent years.

Fodors.com, with 3.2 million unique visitors (up 9 percent) in May, tumbled to 15th place in the travel category, according to comScore.

“Internet Brands has a proven history of navigating legacy brands to strong growth in the digital world,” said Bob Brisco, chief executive at Internet Brands.