Union Pacific Corp. agreed to acquire Norfolk Southern Corp. in a cash-and-stock transaction valued at $85 billion, forming a transcontinental rail behemoth in what stands to be the industry’s largest deal ever.

Union Pacific and Norfolk Southern are in merger talks to create the largest railroad in North America that would connect the East and West Coasts.

Union Pacific will acquire Norfolk Southern in an $85 billion deal, creating the first U.S. transcontinental railroad with service spanning 50,000 miles across 43 states.