Big Sur is located 147 mi (237 km) south of San Francisco, along the Pacific Ocean coast. The term Big Sur generally refers to the town of Big Sur and its surrounding area. The permanent population is considered low, however, thousands of visitors travel to the area each year to watch the grey whale migrations from the Big Sur coastline. The Big Sur International Marathon, held annually in April is the largest rural marathon in the world. Beginning in Big Sur, the marathon track winds through California's redwood forests into Carmel, which offers spectacular views of the Pacific Ocean. Hiking, biking, camping and fishing opportunities are available year-round for visitors to engage in while exploring Julia Pfeiffer Burns and Andrew Molera State Park. The Sand Dollar Beach, which boasts the longest stretch of sandy beach in the area, offers year-round surfing opportunities.