Brightline West is betting it can build the first true high-speed rail line in the U.S. But the company says costs are rising, despite its best efforts to keep them down.

The leaders of California's high-speed rail project say they've learned from past mistakes. But the troubled megaproject faces an uncertain future with $4 billion in federal funding tied up in court.

The NextGen Acela trains, as Amtrak calls them, are faster and lighter than the current fleet. They're scheduled to start revenue service along the Northeast Corridor on Thursday.

The White House hopes to jumpstart high-speed rail in the U.S. with money from the Bipartisan Infrastructure Law. Much of the funding announced this week will go to projects in Nevada and California.