Mugu Lagoon is a salt marsh located within the Naval Base Ventura County at the foot of the Santa Monica Mountains in Ventura County, California. The lagoon extends for 4.3 miles parallel to a narrow barrier beach. The first European to come ashore here was Juan Rodríguez Cabrillo on October 10, 1542. Cabrillo was the first European to visit …Mugu Lagoon is a salt marsh located within the Naval Base Ventura County at the foot of the Santa Monica Mountains in Ventura County, California. The lagoon extends for 4.3 miles parallel to a narrow barrier beach. The first European to come ashore here was Juan Rodríguez Cabrillo on October 10, 1542. Cabrillo was the first European to visit present-day California, and he named the lagoon Mugu after Muwu, which is Chumash meaning "beach" or "seashore". When the Europeans first discovered the lagoon, it functioned as the capital village of the Chumash Indians settled around Point Mugu.