Juan Rodriguez Cabrillo was the first known explorer of the California coast. Around 1519, he fought for the conquest of Mexico with the famous conquistador Hernan Cortes. By 1542, Cabrillo was exploring the California coast under the Spanish flag, hoping to find wealthy cities or Cibola. He reached San Diego bay, on September 28, 1542, naming it "San Miguel". Within a few days, Cabillo departed San Diego to explore the uncharted coast line of California. While he died unexpectedly on January 3, 1543, his chief pilot, Bartolomé Ferrelo, continued the trip northward and reached the Mendocino coast.