The highway that winds along the coast of Marin County offers some of California’s most magnificent vistas, with the deep blue Pacific Ocean glittering through veils of fog. But for a handful of travelers, the views aren’t the prize.

At one blink-and-you’ll-miss-it pullout is a natural spring that draws people from across the San Francisco Bay Area, some of whom drive hours through traffic to get there. Many of them reject water from any other source and drink only what they say is “liquid gold” that gushes from the copper pipes of Red Rock Spring.

“To me, it feels more alive,” said Samantha Reich, who collected 50 gallons in water-cooler jugs that she strapped into her sedan with seatbelts on a recent morning.

Ms. Reich, 27, is among a small number of spring water aficionados who believe untreated water, or “raw water,” contains enriching minerals that are removed from tap water during the purification process.

Many of the spring’s die-hard fans are part of the so-called health freedom movement, which opposes government public health interventions, including vaccine mandates, pasteurized milk and fluoridated water. They now have a powerful ally in Robert F. Kennedy Jr., who espouses many of the same views, including opposition to fluoridated water, and who is President-elect Donald J. Trump’s pick to lead the Health and Human Services Department. (Mr. Kennedy has yet to say whether he advocates drinking raw water.)