With over 2.5 million visitors per year,[2] it is one of the five most-visited state parks in California, hosting swimmers, campers, kayakers, birders, fishermen, bicyclists, sunbathers, surfers, and the sacred Native American site of Panhe.

[5] In the early 1900s, the O'Neills leased the area around the San Onofre train station to Norm Haven, where he oversaw the production of beans, melons, lettuce, and other winter crops.

[6] The Haven' Ranch area included at least one Catholic Church, a school, and travelers along the Coast Highway (completed in 1929) could stop at Frank Ulrich's cafe and service station.

The village that once existed in the San Onofre creek area was demolished to make way for the I-5 freeway in 1960, though the Marines established housing in the hills to the north of the former train stop starting in the 1970s.

On November 10, 2016, the Transportation Corridor Agency abandoned plans to build a six-lane toll highway through San Onofre State Beach, other nearby sensitive environmental areas, and certain Native American cultural sites.

The abandonment of this route for the toll road was part of an agreement ending several lawsuits filed by the California attorney general and a coalition of environmental groups that sought to block the project.

[9] Surfers using redwood boards have visited San Onofre since at least the 1940s, including Lorrin "Whitey" Harrison, Don Okey, Al Dowden, Tom Wilson, and Bob Simmons.