Hyperloop Transportation Technologies plans to break ground on a section of Elon Musk's Hyperloop early next year. From National Geographic:
This (five mile) stretch, near the new town of Quay Valley along Interstate-5 midway between Los Angeles and San Francisco, is estimated to cost $100 million and could start carrying passengers in 2018 after extensive safety testing.
“We look at it as a metro system,” says Dirk Ahlborn, head of Hyperloop Transportation Technologies or HTT, which is building the California project. “We envision a network” in the United States and elsewhere, he says, calling trains a “dinosaur industry” and high-speed rail too expensive.