The explorer who explored the California coast in the 18th century was Juan de Fuca.

Juan de Fuca, a Greek navigator in Spanish service, is best known for his exploration of the Pacific Northwest coast in the late 16th century. However, his name is often associated with the Strait of Juan de Fuca, which separates Vancouver Island from the Olympic Peninsula. His explorations in the region helped pave the way for later European expeditions. In the 18th century, significant exploration along the California coast was conducted by Spanish explorers, notably the voyages led by explorers such as Sebastián Vizcaíno, who mapped the coastline in 1602 and played a key role in the early Spanish missions in California. These explorations led to the establishment of Spanish missions and settlements that shaped California's history and cultural landscape.