California Historical Landmark 236: First Ship into San Francisco Bay
NO. 236 ENTRANCE OF THE SAN CARLOS INTO SAN FRANCISCO BAY – On August 5, 1775, the Spanish packet San Carlos, under the command of Lieutenant Juan Manuel de Ayala, became the first ship to enter San Francisco Bay. His crew spent a month and a half surveying the bay from its southernmost reaches to the northern end of present-day Suisun Bay. The San Carlos departed September 18, 1775.