The ceremony in Fresno today comes amid challenges from Central Valley farmers and communities in the train's path who have sued to block the project. Republican members of Congress vow to cut funding.
State officials say once it's built, the USD 68 billion train system will whisk travellers at 320 kph between Los Angeles and San Francisco in less than three hours.
Dan Richard of the California High-Speed Rail Authority says it will be a model for the nation.
Jeff Denham, a Central Valley Republican in Congress, says the train won't be fast enough or carry enough riders.