Catherine Breed, a marathon swimmer from Mill Valley, completed a 900-mile open-water swim along California’s coast on Sunday. The four-month effort began at the Oregon border on July 1 and ended earlier than her planned November arrival in Mexican waters.

Breed, 33, covered more than 10 miles a day on average through cold, unpredictable Pacific waters. Her route took her past the Golden Gate Bridge and Monterey Bay’s kelp forests, then around Point Conception near Santa Barbara.

Supporters followed the swim online and gathered to cheer her at meeting points. Breed said their encouragement helped her return to the water day after day. The expedition, called Swim California, involved a team operation.